Comparing the timeliness and adequacy of antenatal care uptake between women who married as child brides and adult brides in 20 sub-Saharan African countries.

CONTEXT: Considering the persistent poor maternal and child health outcomes in sub-Saharan Africa (SSA), this study undertook a comparative analysis of the timing and adequacy of antenatal care uptake between women (aged 20-24 years) who married before age 18 and those who married at age 18 or above.
METHOD: Data came from Demographic and Health Surveys of 20 SSA countries. We performed binary logistic regression analysis on pooled data of women aged 20-24 (n = 33,630).
RESULTS: Overall, the percentage of child brides in selected countries was 57.1%, with the lowest prevalence found in Rwanda (19.1%) and the highest rate in Chad (80.9%). Central and West African countries had the highest prevalence of child marriage compared to other sub-regions. Bivariate results indicate that a lower proportion of child brides (50.0%) had 4+ ANC visits compared to the adult brides (60.9%) and a lower percentage of them (34.0%) initiated ANC visits early compared to the adult brides (37.5%). After controlling for country of residence and selected socio-economic and demographic characteristics, multivariable results established significantly lower odds of having an adequate/prescribed number of ANC visits among women who married before age 15 (OR: 0.63, CI: 0.57-0.67, p<0.001), and women who married at ages 15-17 (OR: 0.81, CI: 0.75-0.84, p<0.001) compared to those who married at age 18+. Similar results were established between age at first marriage and timing of first ANC visit. Other interesting results emerged that young women who married earlier than age 18 and those who married at age 18+ differ significantly by several socio-economic and demographic characteristics.
CONCLUSION: Efforts to improve maternal and child health outcomes in SSA must give attention to address the underutilization and late start of antenatal care uptake among child brides.

Introduction

Targets 3.1; 3.3; and 5.3 of the United Nations’ Sustainable Development Goals (SDGs), respectively aim to reduce the global maternal mortality ratio to less than 70 per 100,000 live births; reduce under-5 mortality to at least 25 per 1,000 live births; and end the practice of child, early and forced marriage by 2030 [1]. While the world has made significant progress on these development indicators, pregnancy-related deaths continue to be a serious public health concern in sub-Saharan Africa (SSA). Pregnancy and the period surrounding it remain highly precarious for millions of women and children in SSA [2,3]. Despite several global efforts, maternal and child health outcomes in the region are still appallingly poor. The risk of SSA women dying from pregnancy-related complications is highest globally, with 533 maternal mortality ratio per 100,000 live births [1,3]. SSA is one of the two world’s regions (the other being South Asia) where it is most dangerous to be a mother. The two regions account for 86% of global maternal deaths, with SSA alone contributing about 68% of the global statistics on maternal mortality. Worse still, the region has the highest lifetime risk of maternal death (1 in 38), as against 1 in 240 in South Asia and 1 in 5,400 in high-income countries [4,5].

Although the world recorded accelerated progress in reducing child mortality during the 2000–2019 period, with 1 in 27 children dying before age five in SSA in 2019 compared to 1 in 11 in 1990 (UNFPA, 2020); nevertheless, more than 5 million under-five children died globally in 2019 alone, and more than 50% of these deaths occurred in SSA. Several factors have been attributed to poor maternal and child health outcomes in SSA, including weak health system [6], environmental factors [7], malnutrition [8], socio-economic and bio-demographic characteristics [9-11] and clinical/medical related factors[12,13]. Additionally, one important risk factor of poor maternal and child health established in the literature is child marriage. A growing body of literature adduced that the social and health consequences of child marriage are enormous. These include maternal-related death during childbirth [14,15], obstetric fistulas [15,16], high risk of premature birth and neonatal and child death and increased risk for sexually transmitted diseases [17,18].

Considering that girls who married early are exposed to a high risk of gender-based violence and abuse due to unequal power relations [19,20], we hypothesised in this study that antenatal care use is lower among women who married before age 18 compared to those who married at adult age 18 or older. While studies have shown that low-cost interventions such as antenatal care (ANC) have been proven to be effective in promoting maternal and child health, ANC uptake in terms of its timeliness and adequacy has been below the World Health Organization’s recommended thresholds in many SSA countries. For instance, scholars have established low quality antenatal care in Ethiopia and Nigeria as in many other SSA countries [20,21].

While young women require timely and adequate antenatal care use because of its usefulness for early detection of pregnancy complications, we posit in this study that young women aged 20–24 who married as child brides (marriage before age 18) are likely to have a late start and inadequate uptake of ANC; however, evidence is sparse on this. Hence, in this study, we did a comparative analysis of timeliness and adequacy of antenatal care use between young women (aged 20–24 years) who married before18 years and those who married at age 18 or older, using datasets from 20 sub-Saharan African countries selected based on geographical difference and availability of recent data.

Literature review and theoretical framework

Early marriage is more common among women of low socio-economic status [22,23]. It is a driving force for early pregnancy, as girls who marry before age 18 are under pressure to prove their fertility quickly [24,25]. It disrupts the normal trajectory of life for young girls by cutting short, in most cases, their schooling and economic opportunities, and consequently reduce their quality of life, and results in lower agency among young women [26]. Also, children of adolescent mothers have a higher risk of low birth weight and subsequent mortality [2,27]. Younger mothers themselves have higher maternal morbidity and mortality outcomes compared to older mothers [28].

Despite the risks involved with pregnancy at very young ages, the literature shows that girls and women in SSA are generally less likely to use antenatal care during their pregnancies [29,30]. Older age at marriage increased the likelihood of institutional delivery for women in Indonesia, while there was a higher likelihood of antenatal care use, institutional delivery and postnatal care use among women who had their first children at above age 20 [31].

A study in Senegal using structural equation modelling found that the age at first marriage and gender-role attitudes mediated the relationship between education and skilled birth attendant use [32]. Also, in Uttar Pradesh, India, women’s age at marriage in addition to religion moderated the effects of literacy and wealth on facility delivery [33]. However, some studies showed that age at first marriage and childbearing had no association with antenatal care utilisation [34,35] while other studies showed increased antenatal care use and early booking among younger mothers [36,37]. This thus shows a lack of consensus in the literature regarding the relationship between age at marriage and antenatal care use.

This study is underpinned by the Andersen Behavioural Model of Healthcare Utilization (ABMHU). The model examines factors that influence healthcare utilization in a population, and classifies them into three categories–predisposing, enabling and need factors. Predisposing factors are those demographic and socioeconomic characteristics that encourage, in this case, antenatal care use for younger women, such as their level of education and other socio-economic characteristics. Enabling factors are those that provide the means for mothers to use maternal healthcare, such as their marital status and household income. Need factors are physiological which make healthcare access necessary and are categorized as perceived need, where the individual recognizes the necessity of accessing healthcare and evaluate need, where the need for medical care has been recognized by health professionals. In this case, the need for antenatal care is recognized and encouraged to ensure safe delivery and the survival of both mother and child.

This study utilized a conceptual framework based on the theoretical insights from ABMHU. We posit that the predisposing factors are demographic and socioeconomic characteristics (such as education, wealth index, occupation, media exposure, and place of residence)which may influence the relationship between antenatal care and age at first marriage. Previous studies have established that the factors that predispose women to use antenatal care during pregnancy include higher educational level and urban residence as well as parity [38,39]. Also, other studies found that women autonomy, marital status and gender-based violence or gender relation serve as enabling factors for reproductive health issues such as maternal health care use and fertility outcomes [40-43]). Based on the theoretical insights drawn from ABMHU, we hypothesised in this study that underutilization and late start of ANC use are more likely among child brides compared to adult-brides.

Materials and methods

Data source

The study used the most recent Demographic and Health Survey (DHS) data of 20 countries selected across the four regional blocs of SSA. Surveys for the selected countries were conducted between 2013 and 2019. As shown in Table 1, the total sample was 33,630 with samples ranging from 227 in South Africa to 4072 in Nigeria. The DHS employs a comparable methodology to elicit demographic and health information from nationally representative samples across countries. A stratified two-stage cluster design sampling technique was employed in selecting representative samples. Enumeration areas (EAs) served as the primary sampling unit while a whole listing of households was done in selected EAs to derive representative samples in each country.

Table 1

Weighted sampled population and percentage distribution of child brides and adultbrides across the selected SSA countries.

Sub-region/ Country	Survey year	Age at first marriage		Sample, n (N = 33,630)
		Child brides (<18 years)	Adult-brides (18 or older)
East Africa
Ethiopia	2016	67.8	32.2	1501
Kenya	2014	42.1	57.9	3098
Rwanda	2014–15	19.1	80.9	862
Tanzania	2015–16	47.6	52.4	1542
Uganda	2016	49.5	50.5	2583
Central and West Africa
Benin	2017–18	47.9	52.1	1,805
Cameroon	2018	57.9	42.1	1191
Chad Republic	2014–15	80.9	19.1	2437
Cote D’Ivoire	2013–14	59.8	40.2	2247
Ghana	2014	53.6	46.4	571
Liberia	2020	55.9	44.1	652
Mali	2018	67.8	32.2	1404
Nigeria	2018	69.7	30.3	4072
Sierra Leone	2019	58.6	41.4	1274
Southern Africa
Lesotho	2014	32.6	67.4	670
Malawi	2015–16	56.2	43.8	3815
Mozambique	2015	68.5	31.5	1028
South Africa	2016	20.1	79.9	227
Zambia	2018	50.1	49.9	1555
Zimbabwe	2015	49.6	50.4	1090
Total (selected SSA countries)		56.5	43.5	33,630

Analysis for this study focused on a group of young women (aged 20-24years) which is mutually exclusively divided into two strata: child brides (those who had their first marriage before age 18) and adult brides (those who had their first marriage at age 18+). We utilized the women’s dataset and restricted analysis to young women aged 20–24 years who were ever married and pregnant at least once. Evidence from the literature supports the use of age-group 20–24 as a typical age category for studies on child marriage[40,44].

Variable measurements

The dependent variable considered in this study was antenatal care (ANC) uptake measured in two ways–(i) timing of ANC start and (ii) adequacy of ANC uptake–the former was defined as early ANC initiation if respondents had the first visit during the first trimester, coded as ‘1’, and ‘0’ otherwise; while the latter was defined as adequate ANC use if respondents had 4+ ANC visits, coded as ‘1’ and ‘0’ otherwise. The ANC grouping of ‘less than 4 visits’ and ‘4+ visit’ is based on the recommendation of the World Health Organization which stipulates the latter category as a minimum required number of visits to ensure optimal maternal health and newborn outcomes. The ANC use relates to the index child (which is the most recent birth). DHS questionnaire captured ANC use in terms of frequency and timing of visits, thus permitting the analysis conducted in this study.

The key explanatory variable in this study is child marriage, measured as marriage before age 18. Those who had their first marriage before age 18 were regarded as child brides while those whose age at first marriage was 18+ were considered as adult brides. We grouped the respondents into three categories: (i) very early marriage at <15 years, (ii) marriage at ages 15–17 years, and (iii) marriage at age 18+’. This was to permit examining variations in antenatal care use between respondents who had very early marriage (at ages less than 15 years) and those who married at ages 15–17, and 18+. Age at marriage was considered as the primary exposure in this study because, in many African societies, marriage is closely linked with first pregnancy and childbirth. Scholars have argued that the strong desire to get pregnant and have children soon after marriage is a significant driver of high fertility in many traditional societies [14,24,45]. We could not use variables such as age at first pregnancy and age at first birth because the former is not available in the DHS while the latter is only available for a few countries. Other independent variables considered in this study based on the reviewed literature and our theoretical/conceptual framework include current age (treated as a count variable), education (categorized as none, primary, and secondary/higher), religion (grouped as Christianity, Islam, and others), occupation (grouped as professional, sales/services, agriculture/others, currently not working), wealth index (categorized as poorest, poorer, middle, richer and richest), media exposure (no exposure, and had exposure), parity (grouped as 1 child, 2 children 3 or more children) and place of residence (urban and rural).

Statistical analysis

Data were pooled from the selected 20 countries with a total sample size of 33,630. We analysed the data at three levels–univariate, bivariate, and multivariable analyses. Percentages, charts and frequencies were presented at the univariate level. We examined the relationship between the outcome measures and the key explanatory variables using the Chi-square test and cross-tabulation at the bivariate level. At the multivariable level, we employed binary logistic regression analysis to examine the statistically significant relationships between the outcome variable and the selected explanatory variables. Binary logistic regression was considered suitable for the analysis considering that the two outcome measures were binary taking the value of 1 if the event of interest happened and 0 otherwise; while the independent variables were categorical. Further, the stringent assumptions of linearity and normality of the dependent variable and the residuals could be relaxed for binary logistic regression, unlike the regression analysis. The binary logistic regression model is based on log transformation of odds whose general equation is of the form:

Where; β0 is the intercept

β is the regression coefficient for the predictor variable Xi

X1-Xn are the predictor variables

is the odds of an event taking place. The ratio of odds of an event occurring in one group to the odds of the same event of interest occurring in the other group is called the odds ratio (OR). It indicates whether the odds of an event happening in one group are different from the odds of the same event taking place in another group, with an OR of 1 implying no difference in the event of interest between a given category of a predictor variable and the reference group.

We explored the predictors of each of the two outcome variables (timing of first ANC visit and adequacy of ANC use) by fitting four binary logistic models. Model 1 was the unadjusted model. Model 2 incorporated the key explanatory variable (age at first marriage) and selected demographic and socio-economic characteristics. Model 3 excluded education and added wealth index to the variables considered in Model 3 (to avoid multicollinearity between education and wealth index). Model 4 is the final model which incorporated all the selected variables into the analysis. The study’s hypothesis was tested with a statistical significance set at p<0.05. At each level of analysis, datasets were weighted to adjust for the over or under-sampling of strata in sample selection. All analysis was done using Stata software (version 14.0). Also, descriptive analyses for the pooled data were weighted to adjust for the differences in sample size across countries. Multivariable analyses were performed with and without the use of sample size weight. Because results were similar with or without the use of sample size weight, only the unweighted multivariable analyses are presented. In the multivariable analysis, normative and largest groups were chosen as the reference categories. South Africa and Tanzania are missing in the regression models due to the fewness of observations.

Results

Descriptive analysis

Fig 1 shows the prevalence of child marriage and Table 1 presents the weighted sampled population and percentage distribution of child brides and adult brides across the selected SSA countries. On average, the percentage of child brides in selected SSA countries was 57.1%. As shown in Fig 1, the prevalence of child marriage varied considerably across countries and was lowest in Rwanda (19.1%) and SA (20.1%) and highest in the Chad Republic (80.9%). Central and West African countries had the highest prevalence of child marriage (47.9%-80.9%) while the percentage of adult brides was highest in the East African countries (32.2%-80.9%).

Fig 1

Percentage of child-brides across selected SSA countries.

Bivariate analysis

Table 2 presents the percentage distribution of age at first marriage by early ANC start; and adequate ANC use (4+ ANC visit). As shown in the table, age at first marriage was significantly associated with the timing of ANC visit (in 7 countries) and adequacy of ANC use in 13 of the countries studied (p<0.05). Overall (for all the selected countries), a slightly lower proportion of child brides initiated ANC visits early compared to the adult brides (34.0% vs. 37.5%). In the same vein, the percentage of child brides (50.0%) who had 4+ ANC visits was lower compared to the adult brides (60.9%). Results from the country-level analysis showed a similar pattern for almost all the selected countries. For instance, compared to the adult brides, the majority of child brides in almost all the countries had a lower proportion of women who initiated antenatal care early except in Rwanda, Benin, Ghana and Liberia. Mozambican dataset had no information on the timing of ANC visits.

Table 2

Percentage distribution of study participants aged 20–24 according to the timing of first ANC visit and number of ANC visit by selected SSA countries.

Sub-region/ Country	% with Early ANC start (at first trimester)			% with adequate ANC use (4+ ANC visit)
	Age at first marriage		Significance (X2)	Age at first marriage		Significance (X2)
	Child brides (<18)	Adult-brides (18+)		Child brides (<18)	Adult-brides (18+)
East Africa
Ethiopia	20.8	19.1	0.63	26.1	35.8	15.34*
Kenya	16.2	21.8	14.94**	48.4	58.8	32.93***
Rwanda	62.6	65.9	0.63	44.8	52.0	2.67
Tanzania	22.2	27.1	4.86	45.3	53.9	11.26**
Uganda	28.8	29.5	0.15	58.2	62.4	4.76
Central and West Africa
Benin	46.8	55.6	13.95**	44.1	57.9	34.21***
Cameroon	32.4	47.2	26.76***	51.8	66.9	27.33***
Chad Republic	28.7	39.9	22.03**	32.1	40.8	12.48**
Cote D’Ivoire	16.5	18.3	1.23	45.3	48.6	2.31
Ghana	55.5	64.1	4.69	74.8	84.5	8.94*
Liberia	66.9	63.4	0.95	76.8	81.0	1.89
Mali	36.1	42.6	5.32	40.1	45.7	3.87
Nigeria	13.0	25.1	90.03***	44.3	70.2	230.22***
Sierra Leone	41.2	38.1	1.23	72.8	73.8	0.15
Southern Africa
Lesotho	29.2	44.4	14.46***	61.37	74.9	13.1**
Malawi	23.0	25.1	2.17	43.84	51.6	21.98***
Mozambique	VNA	VNA	VNA	46.3	54.8	6.13*
South Africa	8.9	47.2	19.1***	53.0	73.8	6.34*
Zambia	39.4	37.8	0.40	58.3	63.0	3.61
Zimbabwe	32.9	38.9	4.36	67.9	78.0	14.29***
Total (pooled data)	34.0	37.5	37.59***	50.0	60.9	386***

***p<0.001

**p<0,01

*p<0.05; VNA: Variable not available.

The bivariate analysis/distribution of the study sample by age at first marriage and according to selected socio-economic characteristics is presented in Table 3. All the selected characteristics significantly varied by age at first marriage (p<0.05), thus showing that girls who married before age 15, those who married at age 15–17 and those who married at 18 or older age were significantly different by several socio-economic and demographic characteristics (including education, religion, occupation, household wealth status, media exposure and place of residence). The results indicate that the highest proportions of respondents aged 20-year-olds (49.1%), those with no formal education (45.7%), Muslim women (44.6%), women in agriculture/other petty occupations (41.4%), those from the poorest households (45.0%), women who had no media exposure (44.5%), multiparous women(48.5%), and rural women had their first marriage at ages 15–17.

Table 3

Percentage distribution of study participants aged 20–24 by age at first marriage and according to selected background characteristics (pooled data analysis).

Variables	% (Frequency)	Age at first marriage			Chi-square
		<15	15–17	18+
Current age
20	20.9(7041)	21.9	49.1	29.0
21	16.1(5423)	15.5	42.5	42.0	1033***
22	21.6(7246)	16.4	40.7	42.8
23	20.6(6917)	13.6	36.8	49.7
24	20.8(7002)	12.9	33.4	53.7
Education
None	24.6(8278)	30.1	45.7	24.2	3569***
Primary	41.4(13929)	14.8	45.3	39.9
Secondary/Higher	33.9(11422)	7.6	30.6	61.8
Religion a
Christianity	66.19(22260)	12.6	39.1	48.3	1309***
Islam	25.55(8592)	26.5	44.6	28.9
Others	2.9(984)	18.6	42.1	39.3
Occupation
Professional	2.42(814)	7.0	24.8	68.1	260***
Sales/Service	37.5(12,625)	18.6	41.1	40.3
Agriculture/others	19.6(6577)	14.9	41.4	43.6
Currently not working	40.5(13.613)	16.5	40.1	43.4
Wealth index
Poorest	22.3(7494)	20.6	45.0	34.4	975.31***
Poorer	22.99(7730)	18.1	43.6	38.3
Middle	20.0(6.796)	16.7	41.6	41.6
Richer	19.2(6448)	12.3	37.5	50.2
Richest	15.7(5262)	10.5	31.4	58.1
Media exposure
No exposure	40.4(13.567)	21.8	44.5	33.7	935.21***
Had exposure	40.5(20007)	12.2	37	50.1
Parity
1	40.6(13567)	4.9	29.2	65.9	5613.03***
2	36.6(12312)	15.0	48.5	36.5
3+	22.8(7672)	37.8	47.5	14.8
Place of residence
Urban	28.8(9674)	11.7	34.8	53.5	585.56***
Rural	71.2(23956)	17.9	42.7	39.4

***p<0.001.

Age at first marriage as a predictor of adequate ANC uptake among married young women in sub-Saharan Africa

Table 4 presents results from the binary logistic regression analysis which examined the association between age at first marriage and adequacy of ANC use while adjusting for the selected control variables. The results from the unadjusted model (Model 1a) showed significantly lower odds of using adequate ANC among women who had first marriage at ages 11 to 17 (OR = 0.51 to 0.80, p<0.05) compared to those who married at 18+.Unadjustedmodel examining the relationship between age at first marriage and adequate ANC use (Model 1b) also yielded similar findings. When the selected socio-economic and demographic characteristics were controlled for (without including country of residence), the association between age at first marriage and both indicators of ANC uptake became insignificant (analysis not shown). However, when the country of residence was incorporated into the model, the analysis showed a significant relationship between age at first marriage and the two indicators of ANC use. Model 2a (Table 5A) which adjusted for country of residence and selected socio-economic and demographic characteristics (excluding wealth index to guide against multicollinearity) indicates that young women who married before age 15 (OR: 0.62, CI: 0.58–0.68, p<0.01) and those who married at ages 15–17 (OR: 0.80, CI: 0.76–0.85, p<0.01) were significantly less likely to have adequate/prescribed number of ANC uptake compared to those who married at age 18+.Model 3a that controlled for country, wealth index and other socio-economic and demographic variables (excluding education) and Model 4a (that incorporated all variables) produced similar findings Further analysis in Model 4a indicates some interesting findings. For instance, results revealed significantly lower odds of using adequate ANC in all countries compared to Nigeria (except Ghana, Lesotho, Liberia, Sierra Leone and Zimbabwe). Also, lower odds of utilizing adequate ANC were established among Muslim and rural women; while higher odds of having the prescribed number of ANC visits were established among women who had media exposure (OR = 1.22, CI: 1.16–1.29, p<0.001), women who had secondary or higher education (OR = 1.87, CI: 1.73–2.02, p<0.001), and among women from richest household (OR = 1.74, CI: 1.58–1.94, p<0.001) compared to those in the respective reference categories.

Table 4

Logistic regression model examining the influence of age at first marriage on adequacy and timing of first ANC among young married women in selected SSA countries.

Variables	Adequacy of ANC use		Timing of ANC start
	Model 1a		Model 1b
	Unadjusted OR	95%CI	Unadjusted OR	95%CI
Age at marriage
10	0.51***	(0.39–0.65)	0.76	(0.57–1.00)
11	0.45***	(0.36–0.56)	0.70***	(0.55–0.88)
12	0.43***	(0.37–0.50)	0.63***	(0.53–0.74)
13	0.45***	(0.40–0.51)	0.51***	(0.45–0.59)
14	0.48***	(0.44–0.52)	0.58***	(0.53–0.64)
15	0.61***	(0.57–0.65)	0.67***	(0.62–0.73)
16	0.67***	(0.62–0.71)	0.77***	(0.71–0.82)
17	0.76***	(0.71–0.81)	0.80***	(0.74–086)
18+ (RC)	1.00		1.00

OR = odds ratio, CI = confidence interval.

Model 1a examined relationship between age at first marriage and early ANC start.

Model 1b examined relationship between age at first marriage and adequate ANC use.

Table 5

A. Logistic regression model examining the influence of age at first marriage and selected characteristics on adequacy/number of ANC visit among young married women in selected SSA countries.

B. Logistic regression model examining the influence of age at first marriage and selected characteristics on timing of first ANC visit among young married women in selected SSA countries.

Variables	Model 2a		Model 3a		Model 4a
	Adjusted OR	95%CI	Adjusted OR	95%CI	Adjusted OR	95%CI
Age at First Marriage
18+ (RC)
15-17 years	0.80***	(0.76-0.85)	0.77***	(0.73-0.82)	0.81***	(0.75-0.84)
<15 years	0.62***	(0.58-0.68)	0.58***	(0.54-0.64)	0.63***	(0.57-0.67)
Country of Residence
Nigeria (RC)
Benin	0.92***	(0.82-1.04)	0.78***	(0.69-0.88)	0.87*	(0.78-0.99)
Cameroon	0.94***	(0.82-1.09)	1.01	(0.88-1.16)	0.94	(0.81-1.08)
Chad	0.52***	(0.47-0.59)	0.42***	(0.38-0.48)	0.46***	(0.42-0.53)
Cote D’ivoire	0.59***	(0.53-0.67)	0.61***	(0.55-0.69)	0.58***	(0.51-0.65)
Ethiopia	0.53***	(0.47-0.61)	0.48***	(0.43-0.56)	0.48***	(0.43-0.56)
Ghana	3.00***	(2.42-3.73)	3.16***	(2.55-3.95)	3.19***	(2.57-3.97)
Kenya	0.71***	(0.64-0.80)	0.76***	(0.68-0.85)	0.73***	(0.66-0.82)
Lesotho	1.51***	(1.25-1.83)	1.74***	(1.45-2.11)	1.52***	(1.26-1.84)
Liberia	2.82***	(2.32-3.43)	2.93***	(2.41-3.56)	2.88***	(2.37-3.51)
Malawi	0.65***	(0.59-0.73)	0.67***	(0.61-0.74)	0.61***	(0.55-0.68)
Mali	0.58***	(0.51-0.67)	0.43***	(0.38-0.50)	0.54***	(0.47-0.62)
Mozambique	0.79**	(0.68-0.92)	0.79***	(0.68-0.92)	0.74***	(0.64-0.68)
Rwanda	0.58***	(0.50-0.69)	0.58***	(0.50-0.69)	0.56***	(0.48-0.67)
Sierra-Leone	2.86***	(2.48-3.31)	2.87***	(2.49-3.32)	2.77***	(2.40-3.21)
Uganda	0.99	(0.88-1.11)	1.05	(0.94-1.17)	0.95	(0.85-1.07)
Zambia	1.05	(0.92-1.21)	1.19*	(1.04-1.36)	1.06	(0.94-1.22)
Zimbabwe	1.49***	(1.27-1.74)	1.71***	(1.46-2.00)	1.49***	(1.28-1.75)
Age
20 (RC)	1
21	1.03	(0.95-1.11)	1.03	(0.96-1.12)	1.02	(0.94-1.10)
22	0.94	(0.87-1.01)	0.93	(0.87-1.00)	0.92*	(0.86-1.00)
23	0.87**	(0.81-0.95)	0.86***	(0.80-0.93)	0.85***	(0.79-0.93)
24	0.89**	(0.83-0.97)	0.86***	(0.80-0.94)	0.86***	(0.80-0.94)
Religion
Christianity (RC)
Islam	0.83***	(0.78-0.89)	0.70***	(0.66-0.75)	0.82***	(0.77-0.88)
Others	0.81**	(0.71-0.93)	0.77***	(067-0.88)	0.82***	(0.71-0.94)
Media Exposure
Not Exposed (RC)
Exposed	1.32***	(1.25-1.39)	1.29***	(1.23-137)	1.22***	(1.16-1.29)
Children Ever born
1 (RC)
2	1.06*	(1.00-1.12)	1.07*	(1.01-1.13)	1.07*	(1.02-1.14)
3+	1.11**	(1.04-1.20)	1.12**	(1.05-1.22)	1.14***	(1.07-1.24)
Residence
Urban (RC)
Rural	0.76***	(0.72-0.80)	0.87***	(0.82-0.93)	0.89**	(0.84-0.96)
Occupation
Not Working
Professional	1.11	(0.95-1.30)	1.13	(0.96-1.32)	1.07	(0.91-1.26)
Sales/Services	1.15***	(1.08-1.24)	1.18***	(1.10-1.27)	1.14***	(1.07-1.23)
Agriculture/Others	1.02	(0.97-1.09)	1.05	(099-1.12)	1.05	(1.00-1.12)
Education
None
Primary	1.73***	(1.61-1.85)			1.67***	(1.56-1.79)
Secondary+	2.05***	(1.91-2.22)			1.87***	1.73-2.02)
Wealth Status
poorest
poorer			1.26***	(1.18-1.35)	1.18***	(1.11-1.27)
middle			1.36***	(1.27-1.47)	1.24***	1.15-1.34)
richer			1.54***	(1.42-1.67)	1.36***	1.26-1.49)
richest			2.02***	(1.83-2.23)	1.74***	1.58-1.94)
*p<0.05; OR = odd ratio; CI = confidence interval.,—Cells are empty where models were not applicable.
Model 2a examined the relationship between age at first marriage and adequacy of ANC use while controlling for selected explanatory variables (excluding wealth status).
Model 3a achieves similar purpose but excludes education variable.
Model 4a examined same relationship while controlling for all the selected explanatory variables.

Age at first marriage as a predictor of timing of ANC start among married young women in sub-Saharan Africa

Results from the binary logistic regression analysis which examined the association between age at first marriage and the timing of ANC initiation are presented in Table 5B. The results from Model 2bwhich controlled for the selected demographic and socio-economic characteristics indicate a significantly lower odds of having early ANC start among women who married before age 15 (OR: 0.76, CI: 0.69–0.83, p<0.001) and those who married at ages 15–17 (OR: 0.90, CI: 0.85–0.96, p<0.05) compared to those who married at age 18+. The results in the final model (Model 4b) further indicate a significantly higher odds of initiating ANC early in all countries (except Kenya and Cote D’Ivoire), among women who had media exposure (OR = 1.12, CI: 1.06–1.20, p<0.001), women with secondary or higher education (OR:1.54, CI: 1.41–1.67, p<0.001) and women in the richest households (OR = 1.72, CI: 1.55–1.92, p<0.001) compared to those in different reference groups. Also, Muslim women had significantly lower odds of initiating early ANC visit (OR = 0.77, CI: 0.71–0.83, p<0.05) compared to their Christian counterparts.

Discussion

The main objective of this study was to examine how two antenatal care indicators (timing of first ANC visit and adequacy of ANC uptake) among young married women aged 20–24 compare between the child brides (women who married before age 18) and adult-brides (women who married at age 18 or above) in 20 sub-Saharan African countries. This study, which is one of the few attempts on the subject matter, is important considering that maternal deaths from pregnancy-related complications remain a serious public health concern in SSA. While antenatal care uptake holds great prospects for good maternal and child health outcomes [2], child brides in SSA face enormous poor health and developmental challenges [14,15], however, there is a dearth of research on the timeliness and adequacy of ANC use among child brides. Thus, we compared the timeliness and adequacy of antenatal care uptake between young women who married as child brides and those who married at adult age.

Our findings indicate that almost three-fifths of young women in selected countries married as child brides. Notwithstanding, there is sub-regional variation in the prevalence of child marriage in the selected countries, with Central and West Africa having the highest percentage of child marriage while East Africa generally had the highest proportion of women who had a first marriage as adults. This finding lends credence to prior research which established higher rates of child marriage in Central and West Africa compared to East Africa [3].

The study established some interesting variations, as many socio-economic and demographic characteristics differ significantly between respondents who married before age 18 and those who married at 18 or older age. These findings indicate that girls who marry at an early age are quite different in very many ways compared to those who marry at a later age. Compared with women with higher socioeconomic status, the prevalence of child marriage was higher among women with low education, women from poor households, women in non-professional occupations and the unemployed, multiparous women, and those in rural areas. It is a major finding from this study that many of the selected socio-economic and demographic characteristics that influence early marriage are also key drivers of poor and inadequate use of ANC in SSA.

Further, comparing the two indicators of ANC uptake, on the one hand, we observed a regional pattern as our bivariate results showed that in most of the selected countries in Central, West and Southern Africa, the percentage of women with early ANC start at the first trimester was significantly lower among child brides compared to the adult-brides. These results were re-echoed by our multivariable analysis. Particularly after adjusting for country of residence, we found that child brides were more likely to initiate ANC visits late compared to the adult-brides. We conjecture two plausible explanations for these findings. First, our data showed that child brides had poor access to media information, a situation that may affect their knowledge about reproductive health issues. Second, even if child brides have adequate knowledge regarding their reproductive health matters and know about the benefits of early ANC start, other findings from our analysis suggest that these women lack appropriate resources to receive adequate ANC from skilled healthcare personnel. As we posited, based on Andersen Behavioural Model of Healthcare Utilization, antenatal care use is largely influenced by women’s socio-economic status. Findings from our analysis show that child brides have low educational attainment and poor socio-economic status, thus lending credence to findings of previous studies [22,23]. Due to their low socio-economic position in the household, child brides are subjected to control [46,47], and their partners/husbands and mothers-in-law wield considerable dominant power in the decision to seek care [9,16].

On the other hand, our bivariate analysis on the adequacy of ANC uptake reveals that overall and in each of the selected countries, a lower proportion of child brides had an adequate/prescribed number of ANC visits compared with adult-brides. These results were supported by the multivariable analysis, as our data indicate lower odds of having an adequate number of ANC visits among child brides compared to their counterparts who married at adult age. These findings reinforce the existing evidence regarding the negative implication of child marriage for maternal healthcare use. As established in extant literature [9,47,48], other factors that influence ANC use, including access to media/information, social isolation, limited access to household resources, poor access to quality care, poor socio-economic status and limited freedom of movement and autonomy in decision-making may play a significant role in these findings.

The concept of early marriage (which is marriage before 18 years in many contexts) is often viewed by scholars as a forced marital dyad [14,19,49]. Other studies have however reported different perspectives on the role of women’s agency and autonomy and argued that early marriage is not just a determinant of poor socio-economic and health outcomes, but rather a viable option or response to it particularly among poor adolescent girls [50-52]. This is perhaps an important reason why similar socio-economic and demographic characteristics were established as drivers of both early marriage and poor ANC use.

The two indicators of antenatal care considered in this study appear to be interconnected, because women who initiated antenatal care visits late also largely have an inadequate number of antenatal care visits, perhaps because they had a late start at the second or third trimester. Besides, the two indicators mainly have the same set of predictors such as education, media exposure, occupation, parity, religion, wealth index, and place of residence. Interventions towards ensuring early ANC start may therefore also lead to adequate ANC uptake among women.

The findings of this study have important policy implications. The observed underutilization and late start of antenatal care use among child brides make them an important sub-group of concern. With a very high proportion of child brides initiating antenatal care late in the second or third trimester as well as having an inadequate number of antenatal care visits to skilled healthcare providers, maternal and child mortality would remain high in SSA. As Izugbara and colleagues [3] noted, pregnancies and their outcomes would remain highly risky for child brides, except there are major interventions to address the problem. Since childbearing is closely linked to marriage in the African contexts [53], and child brides lack what it takes to negotiate safer and protected sex, millions of them would continue to get pregnant annually in a precarious condition. Moreover, considering that child marriage is mainly common among women of low socio-economic status [22,23], child brides largely lack economic resources and are unable to make independent decisions to seek healthcare. They are therefore at the mercy of their partners. We, therefore, recommend programmes and interventions that would lead to delayed marriage among girls, such as free and compulsory education. These would achieve two purposes–socio-economic empowerment of women and delay of first marriage among girls.

While interpreting the results of this study, it is important to consider some drawbacks, including the use of cross-sectional data which limits analysis only to exploring association. Also, the study was constrained to the analysis of variables available in the DHS, which hinders the investigation of culturally-laden drivers of early marriage and antenatal care non-use. Lastly, the datasets were not collected same year in different countries, albeit, this would not invalidate our findings, as evidence from the literature and our results demonstrate tardy progress in reducing child marriage in the selected countries during the period under study. Notwithstanding these limitations, the study has some strength and offers deeper insights on the implication of early girl-child marriage for a late start and inadequate ANC uptake. Besides, we analysed multi-country DHS data that utilized similar methodologies across the country, thus permitting comparability of study findings.

Conclusion

This study concludes that efforts to reduce SSA’s high rate of newborn and maternal mortality in line with the relevant SDG targets must give considerable attention to address the underutilization and late start of antenatal care uptake among child brides. Besides, considering the precarious conditions of child brides, including low education, poor employment prospects and generally low socio-economic status, interventions to improve the situations of girl-children must be a major focus and consideration of policymakers. Ultimately, there is the need to end girl-child marriage in SSA in line with target 5.3 which aims to end the practice of child, early and forced marriage by 2030.

20 Jul 2021

PONE-D-21-15115

Comparing the timeliness and adequacy of antenatal care uptake between women who married as child-brides and adult-brides in 20 sub-Saharan African countries

PLOS ONE

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Additional Editor Comments:

The reviewers note that the manuscript is well written, but highlight important concerns - that must be addressed carefully. Most importantly, reviewer 2 notes that your conclusions are NOT supported by the presented data. After controlling for a number of socio-economic and demographic characteristics (in particular woman’s education), the association between age at marriage and ANC use disappears (or at least loses significance / 95% CIs cross 1). This is reflected in Tables 4 and 5. However, in your discussion you indicate that the results are evidence that age at marriage is associated with ANC use (which it is only in bivariate analyses) in a way that implies causality. There is a sense of picking and choosing which results to discuss that fit an established narrative about the harms of early marriage, rather than examining the evidence objectively. Clearly, this is not acceptable. A more accurate conclusion may be that a number of socio-economic and demographic characteristics are associated both with age at marriage and ANC use, and as such may be driving both early marriage and poor ANC use. This is not addressed in the discussion or conclusion. According to Reviewer 2, you can not confidently conclude that ending child marriage will improve ANC use among young women based on the results as they stand.

A second important concern is that the category of 'child marriage' (and 'child bride') is adopted rather uncritically, with an assumption that all marriages under 18 years are inherently forced and that women have no autonomy in these unions, as an explanation for why poorer ANC use can be expected amongst younger women. I can recommend this paper by Schaffnit et al below (of which I am a coauthor) for a more grounded perspective on the drivers of early marriage and the role of women's agency. Your paper should consider why early marriage itself may not be best understood as a root cause of hardship, but rather a response to it - rather than have a forgone conclusion: Schaffnit SB, Wamoyi J, Urassa M, Dardoumpa M, & Lawson DW. (2020). When marriage is the best available option: perceptions of opportunity and risk in female adolescence in Tanzania. Global Public Health.

Both reviewers also make numerous suggestions about the analysis, which all must be considered fully. If you choose to revise and resubmit the manuscript I will examine these issues myself in close detail. For now, it is clear that author responses to a number of points are required before we can proceed.

Thank you for submitting and I hope, despite some critical feedback, you find these points constructive and see a way forward with the paper!

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Reviewer #1: This is a useful piece of work. I suggest the following revisions:

1. The authors should add footnotes to show what each model in Tables 4 and 5 represent. The category first category for age in Table 3 (20) is different from that of Table 4 and 5 (<20). This should be corrected.

2. The authors pooled data from 20 SSA countries. It is not clear how weighting was applied. I do not mean the DHS sample weights but I mean the data weighting after pooling as you deal with multiple countries with wide variation in their population? (https://academic.oup.com/jn/article/128/10/1672/4723073?login=true)

3. The use of binary logistic regression does not cater for the hierarchical structure of the DHS datasets. I suggest the use of multilevel logistic regression

4. The authors did not control for country and survey year in their regression models. How do you deal with the heterogeneity in the 20 countries and the between and within country variations in the results?

5. I suggest presenting results for the final model of the regression outputs in the write-up of the results Again, using OR for both crude and adjusted results is confusing.

6. It is not clear why the authors chose to limit their study to DHS datasets up to 2018 when there are more recent datasets for countries like Liberia and Sierra Leone (All published in 2019).

7. I suggest the authors provide detailed information on the coding of the covariates in the methods.

8. It will be informative that the authors indicate what influenced the choice of the referent categories for the regression models. For instance, why was Christianity a referent category and Islam? I don’t want to assume that these were chosen because they were the first categories of the variables. The authors may refer to this link in deciding which category to choose as referent https://www.theanalysisfactor.com/strategies-dummy-coding/

9. Evidence from literature supports the use of age-group 20-24 as a typical age category for studies on child marriage (Godha et al., 2013; Yaya et al., 2019). The citation for this statement is different from the rest.

Reviewer #2: This was a well and clearly written paper that explores an important topic. The authors present results of original research and use appropriate data and analysis to address their research questions. My main concern is with the interpretation of results and discussion, which need to be revised before this manuscript can be recommended for publication.

Major comments

1. Introduction:

a. The authors mention that health risks of ‘child marriage’ are enormous, but surely these are the risks of early pregnancy, regardless of marriage? Some elaboration is needed here on why the authors chose to focus on age at marriage and not age at pregnancy or first birth as their primary exposure.

b. A clear conceptual framework is not developed. Which characteristics of early marriage do the authors think would be associated with poorer ANC use? They mention low SES, lower educational attainment, and pressures to prove fertility as factors that are associated with early marriage – but these are all factors that may be leading to early marriage?

2. Methods:

a. If the DHS allows, then why not measure age at marriage continuously to see variation between very early marriage (e.g., 13 years) and marriage closer to 18 years (e.g., 17 years). Marriage at 17 years is likely more similar to marriage at 18 years than marriage at 13 years, and as such there may be different effects on health seeking behaviour within the group under 18 years.

3. Results:

a. The authors state that age at marriage ‘was significantly associated with the timing of ANC visit and adequacy of ANC use in most countries studied’ – however, this is misleading. Table 2 shows that these findings were significant (p<0.05) for 7 out of 19 countries for early ANC start (i.e., 37% of the sample), and 11 out of 20 for 4+ ANC visits (55% of total sample), which I would not say is ‘most countries’. For initiating ANC visits early, the overall difference across all countries between those married before 18 years and those married at 18+ years is slim (34% vs 38%). There is a bigger difference for those who had 4+ ANC visits, but this too is limited to bivariate analyses.

b. I think the most interesting findings in this manuscript lie in Table 3. Here, the authors show that girls/women who marry before age 18 and those who marry at 18+ years differ significantly by a number of socio-economic and demographic characteristics: including education, occupation, household wealth index, media exposure, parity and urban/rural residence. This perhaps indicates, and is not reflected in the authors’ discussion at all, that girls who marry earlier are quite different in a number of ways to those who marry later and that these socio-economic and demographic characteristics may perhaps be driving BOTH early marriage as well as ANC use (and as such, that the relationship between age at marriage and ANC use is confounded by these socioeconomic and demographic characteristics). I suggest this is pulled out more in both the Results and Discussion sections.

c. My comment above is further supported by the authors’ main findings in the regression models. Firstly, education appears to drive the effect between age at marriage and adequate (4+ times) use of ANC. The association is also partially driven by other socio-economic and demographic factors included in the model – or in other words, all these factors are correlated with both age at marriage and adequate ANC use. Secondly, there is no association between age at marriage and timing of ANC use once socio-economic and demographic factors are controlled for. Again, the relationship between age at marriage and timing of ANC use appears to be driven by these socio-economic and demographic factors that are included in the models. These findings need to be brought out substantially in the discussion.

4. Discussion:

a. The discussion would be richer if it included details on the variation in age at marriage and ANC use across all SSA countries, instead of generalised statements like ‘almost three-fifths of young women in selected countries married as child brides’ as these can be misleading – which countries are they referring to? Again, it would be a lot more valuable to see variation in age at marriage under 18 years – how many of these women were marrying at age 17 (which is not so different from 18) and how many of them were marrying below that age, and especially how many (and in which countries) are marrying at very young ages (e.g., 13-14).

b. Equally, it would be valuable to examine age at first birth/pregnancy, and how that varies across regions and countries, as that is perhaps more directly related to ANC use than age at marriage.

c. A main strength of this paper is that the authors show which socio-economic and demographic characteristics of women are associated with ANC use, and which of these are also associated with early marriage. They in fact find no evidence to support their prediction that early marriage is associated with poor ANC use. However, in their discussion, they choose to present their bivariate findings instead of results from their final models which is misleading. Their recommendations are based on findings which they have themselves stated are not significant (p<0.05, Odds Ratios close to 1, and 95% confidence intervals crossing 1). I suggest this is revised.

d. Much of the literature cited in the discussion seems to suggest that poor educational attainment, low SES etc. are all associated with early marriage, but they do not consider that these factors may be what also lead to poor ANC use (e.g., issues of access and information may affect ANC use independent of age at marriage, and this is in fact shown in their regression models.)

e. Page 13, first paragraph, last sentence – more detail needed. Each of these factors should be discussed to show how they relate to both age at marriage and ANC use. I also think it is important to include a discourse here on the finding that after controlling for a number of socio-economic and demographic factors, age at marriage was in fact found to have no association with either measure of ANC use; and further that these socio-economic and demographic factors were strongly associated with ANC use and age at marriage. Why do the authors think these socio-economic and demographic factors are associated with both their exposure and outcome variables, and what are the possible pathways for these associations?

f. The authors do not give thought to why women might be marrying early and ignore contexts where women may be choosing to marry before age 18 (see Schaffnit, Urassa, Lawson, 2019; Stark, 2018; and others – citations given below). As such, there is some confusion between early marriage and forced marriage – whereas not all marriages before age 18 years are forced, or against the wishes of girls/women. By assuming that marriages before 18 years are forced or against women’s wishes, the authors take autonomy/agency away from these women, and simultaneously consider, for example, women marrying at age 18 (or slightly older) to have full agency, some of whom may not be very different to women aged 17 years and may also be entering marriages against their wishes. Again, important nuance would be added to this paper if the age at marriage variable distinguishes between very young girls and those who are closer to 18 years but still considered as ‘children’, as well as between those in the 18+ category (e.g., between an 18 year old and a 30 year old). I also recommend thinking a bit further about contextual differences in the meaning of ‘childhood’ as the definition of childhood can vary cross-culturally (see Hart, 2006; Rosen, 2007 - citations given below).

g. Further, a conceptual framework outlined in the introduction may help highlight which characteristics of marriage the authors expect will lead to poorer ANC use, distinguishing between, for example, forced marriage (and related loss of autonomy/agency), very early marriage (for example 13- or 14-year-olds), and age at first birth (and other aspects). As it stands, the authors are conflating these concepts under the umbrella of ‘child marriage’ / ‘marriage under 18-years’.

Minor comments

1. Terminology: I would suggest using the term ‘age at marriage’ throughout the paper to refer to the main exposure, instead of ‘child/adult marriage’. For example, in the Results section when discussing bivariate analyses, I think the authors mean ‘age at marriage’ was associated with ANC visits, not ‘child marriage’. Here, using the term ‘child marriage’ indicates that only marriage before 18 years is associated with ANC and not marriage at 18+ years – whereas the indicator that the authors are using is actually ‘age at marriage’. Using one term to describe their variable will add consistency to the manuscript.

2. Can this analysis be carried out using a linear variable for age at marriage – what is the effect of very early marriage (e.g., 13-15 year olds) versus 16-17 year olds versus 18-19 year olds? This would help differentiate the effects of very early marriage to marriage at ages closer to 18 years.

3. Abstract: The abstract needs to reflect the main findings - i.e., no association between age at marriage and ANC use after controlling for certain socio-economic and demographic variables.

4. Introduction:

a. What about younger unmarried woman - what is the rationale behind restricting analyses to married women, and why don’t the authors directly explore effects of early childbearing? An explanation can be added to the introduction.

b. The authors state that a high risk of gender-based violence among women married before age 18 would lead to lower ANC use – this may be true, but does not seem relevant to this paper. If it is relevant, the authors should clarify the links between age at marriage, gender-based violence and ANC use and elaborate on this relationship in detail, citing relevant literature.

3. Methods:

a. Clarity needed on the ANC measure for 4+ visits - what time frame does this refer to, the previous/most recent pregnancy?

4. Discussion:

a. Similar to minor comment 4b above: Stark statements are made about domestic violence and abuse with no clear explanation or rationale about how this relates to ANC use and early marriage – this topic is not explored in the authors' analyses, and these posited associations are not supported with relevant literature. I suggest this is revised either to fully explore how violence against women is associated with both ANC use and early marriage, with relevant citations, or the emphasis on violence against women is minimised as this is not directly relevant to this paper, i.e., the authors do not test the association between violence, ANC use and age at marriage.

b. The authors use causal terminology such as ‘child brides may initiate ANC visit late due to poor knowledge about their health issues’ without providing any supporting literature. Some of these statements come across as opinions and/or value judgements – citations are needed here, and even when literature is cited the different contexts of different studies (especially the age of women / age at marriage) need to be highlighted.

5. Papers of potential interest:

Dixon-Mueller, R. (2008). How young is “too young”? Comparative perspectives on adolescent sexual, marital, and reproductive transitions. In Studies in Family Planning (Vol. 39, pp. 247–262). Stud Fam Plann. https://doi.org/10.1111/j.1728-4465.2008.00173.

Hart, J. (2006). Saving children: what role for anthropology?, 1968(1), 131–134.

Rosen, D. M. (2007). Child Soldiers, International Humanitarian Law, and the Globalization of Childhood. American Anthropologist, 109(2), 296–306. https://doi.org/10.1525/aa.2007.109.2.296

Schaffnit, S. B., Hassan, A., Urassa, M., & Lawson, D. W. (2019, February). Parent–offspring conflict unlikely to explain ‘child marriage’ in northwestern Tanzania. Nature Human Behaviour. Nature Publishing Group. https://doi.org/10.1038/s41562-019-0535-4

Schaffnit, S. B., Urassa, M., & Lawson, D. W. (2019). “Child marriage” in context: exploring local attitudes towards early marriage in rural Tanzania. Sexual and Reproductive Health Matters, 27(1), 93–105. https://doi.org/10.1080/09688080.2019.1571304

Stark, L. (2018a). Early marriage and cultural constructions of adulthood in two slums in Dar es Salaam. Culture, Health and Sexuality, 20(8), 888–901. https://doi.org/10.1080/13691058.2017.1390162

Stark, L. (2018b). Poverty, Consent, and Choice in Early Marriage: Ethnographic Perspectives from Urban Tanzania. Marriage and Family Review, 54(6), 565–581. https://doi.org/10.1080/01494929.2017.1403998

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8 Oct 2021

Response to reviewers’ comments

PONE-D-21-15115

Comparing the timeliness and adequacy of antenatal care uptake between women who married as child-brides and adult-brides in 20 sub-Saharan African countries

PLOS ONE

Comments

The reviewers note that the manuscript is well written, but highlight important concerns - that must be addressed carefully. Most importantly, reviewer 2 notes that your conclusions are NOT supported by the presented data. After controlling for a number of socio-economic and demographic characteristics (in particular woman’s education), the association between age at marriage and ANC use disappears (or at least loses significance / 95% CIs cross 1). This is reflected in Tables 4 and 5. However, in your discussion you indicate that the results are evidence that age at marriage is associated with ANC use (which it is only in bivariate analyses) in a way that implies causality. There is a sense of picking and choosing which results to discuss that fit an established narrative about the harms of early marriage, rather than examining the evidence objectively. Clearly, this is not acceptable. A more accurate conclusion may be that a number of socio-economic and demographic characteristics are associated both with age at marriage and ANC use, and as such may be driving both early marriage and poor ANC use. This is not addressed in the discussion or conclusion. According to Reviewer 2, you can not confidently conclude that ending child marriage will improve ANC use among young women based on the results as they stand.

Response

Thank you for the comments. We have now revised all sections of the manuscript. The multivariable analysis that was done previously showed an insignificant relationship between age at first marriage and antenatal care use. However, based on reviewers’ comments, we have undertaken a fresh analysis where we re-categorised age at first marriage to three groups in order to distinguish between respondents who married at a very early age (<15 years) and those who married at ages 15-17 and 18+. Our fresh analysis also controlled for the country of residence, and the results now show a significant relationship between age at first marriage and the two indicators of antenatal care uptake. The significant relationship between the outcome and exposure variables was as a result of re-categorizing age at first marriage and as well controlling for country of residence. The results demonstrate some between-country variations. We have discussed these findings in our discussion section.

Comments

A second important concern is that the category of 'child marriage' (and 'child bride') is adopted rather uncritically, with an assumption that all marriages under 18 years are inherently forced and that women have no autonomy in these unions, as an explanation for why poorer ANC use can be expected amongst younger women. I can recommend this paper by Schaffnit et al below (of which I am a coauthor) for a more grounded perspective on the drivers of early marriage and the role of women's agency. Your paper should consider why early marriage itself may not be best understood as a root cause of hardship, but rather a response to it - rather than have a forgone conclusion: Schaffnit SB, Wamoyi J, Urassa M, Dardoumpa M, & Lawson DW. (2020). When marriage is the best available option: perceptions of opportunity and risk in female adolescence in Tanzania. Global Public Health.

Response

We have read the suggested paper by Schaffnit et al (2020) as well as some other relevant publications and have considered the critical points raised as reflected in our revised texts presented below:

The concept of early marriage (which is marriage before 18 years in many contexts) is often viewed by scholars as a forced marital dyad (Adhikari, 2018; Mobolaji et al., 2020; Omariba & Boyle, 2007). Other studies have however reported different perspectives on the role of women’s agency and autonomy and argued that early marriage is not just a determinant of poor socio-economic and health outcomes, but rather a viable option or response to it particularly among poor adolescent girls (Al-Eisawi et al., 2021; Schaffnit et al., 2019; Schaffnit et al., 2020). This is perhaps an important reason why our analysis established similar socio-economic and demographic characteristics as drivers of both early marriage and poor ANC use.

Comments

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Response

The data used for the manuscript are from Demographic and Health Survey. The datasets are available for public use. We have inserted the texts below into our cover letter:

Data for this manuscript are publicly available on the website of Demographic and Health Survey program (www.dhsprogram.org).

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: This is a useful piece of work. I suggest the following revisions:

1. The authors should add footnotes to show what each model in Tables 4 and 5 represent. The category first category for age in Table 3 (20) is different from that of Table 4 and 5 (<20). This should be corrected.

Response

The analysis covered women aged 20-24. We used the variable as a count measure. This is now consistently used in all the tables.

We have provided footnotes to indicate what each model represents.

Comments

2. The authors pooled data from 20 SSA countries. It is not clear how weighting was applied. I do not mean the DHS sample weights but I mean the data weighting after pooling as you deal with multiple countries with wide variation in their population? (https://academic.oup.com/jn/article/128/10/1672/4723073?login=true)

Response

We have included country sample weight in DHS cross countries analysis. According to Peng, et.al, (1998) in Maternal Nutritional Status Is Inversely Associated with Lactational Amenorrhea in Sub-Saharan Africa: Results from Demographic and Health Surveys II and III1–5, descriptive analyses for the pooled data were weighted to adjust for the differences in sample size across countries. The sample size weight was created from the equation: 1/(7.[nC/nT]), where nC is the sample size for each country and nT is the sample size for the pooled data.

Multivariable analyses were performed with and without the use of sample size weight. Because results were similar with or without the use of sample size weight, only the unweighted analyses are presented for the pooled analyses. We have included this information in the revised manuscript.

Comments

3. The use of binary logistic regression does not cater for the hierarchical structure of the DHS datasets. I suggest the use of multilevel logistic regression

Response

Thank you for this comment. Objective of this manuscript does not include exploring the influences of contextual characteristics on the outcome measures. This would be a good research question to interrogate in another manuscript.

Comments

4. The authors did not control for country and survey year in their regression models. How do you deal with the heterogeneity in the 20 countries and the between and within country variations in the results?

Response

The between and within country variations are expected in the results. The revised analysis has now considered country as a variable in our regression models.

Comments

5. I suggest presenting results for the final model of the regression outputs in the write-up of the results Again, using OR for both crude and adjusted results is confusing.

Response

We have presented results for only the final model of the regression outputs in the write-up. UOR has now been used for the crude model and AOR is now used for the adjusted model.

Comments

6. It is not clear why the authors chose to limit their study to DHS datasets up to 2018 when there are more recent datasets for countries like Liberia and Sierra Leone (All published in 2019).

Response

More recent datasets for selected countries have now been used in the revised analysis.

Latest Liberia and Sierra Leone already downloaded and added to the new analysis.

Comments

7. I suggest the authors provide detailed information on the coding of the covariates in the methods.

Response

We have provided detailed information in the method section on the coding of the selected variables.

Comments

8. It will be informative that the authors indicate what influenced the choice of the referent categories for the regression models. For instance, why was Christianity a referent category and Islam? I don’t want to assume that these were chosen because they were the first categories of the variables. The authors may refer to this link in deciding which category to choose as referent https://www.theanalysisfactor.com/strategies-dummy-coding/

Response

Thank you for this comment. In the multivariable analysis, normative and largest groups were chosen as the reference categories. We have included this information in the text

Comments

9. Evidence from literature supports the use of age-group 20-24 as a typical age category for studies on child marriage (Godha et al., 2013; Yaya et al., 2019). The citation for this statement is different from the rest.

Response

We have formatted the citations in accordingly

Response Comments

Comments

Reviewer #2: This was a well and clearly written paper that explores an important topic. The authors present results of original research and use appropriate data and analysis to address their research questions. My main concern is with the interpretation of results and discussion, which need to be revised before this manuscript can be recommended for publication.

Major comments

1. Introduction:

a. The authors mention that health risks of ‘child marriage’ are enormous, but surely these are the risks of early pregnancy, regardless of marriage? Some elaboration is needed here on why the authors chose to focus on age at marriage and not age at pregnancy or first birth as their primary exposure.

Response

Thank you. In response to this comment, we have provided some elaboration and explanation for focusing on early marriage/age at marriage. The revision is as shown below:

Age at marriage was considered as the primary exposure in this study because, in many African societies, marriage is closely linked with first pregnancy and childbirth. Scholars have argued that the strong desire to get pregnant and have children soon after marriage is a significant driver of high fertility in many traditional societies (Mobolaji et al., 2020; Spagnoletti et al., 2018).

Comments

b. A clear conceptual framework is not developed. Which characteristics of early marriage do the authors think would be associated with poorer ANC use? They mention low SES, lower educational attainment, and pressures to prove fertility as factors that are associated with early marriage – but these are all factors that may be leading to early marriage?

Response

A relevant conceptual framework has been included in the revised manuscript. This is underpinned by the Andersen Behavioural Model of Healthcare Utilization. Based on this theory, we posit that antenatal care use is largely influenced by women’s low socio-economic status, lower educational attainment, etc. However, findings from our analysis show that early marriage is also associated with some of women characteristics such as low socio-economic status. We have discussed these findings in our discussion section.

Comments

2. Methods:

a. If the DHS allows, then why not measure age at marriage continuously to see variation between very early marriage (e.g., 13 years) and marriage closer to 18 years (e.g., 17 years). Marriage at 17 years is likely more similar to marriage at 18 years than marriage at 13 years, and as such there may be different effects on health seeking behaviour within the group under 18 years.

Response

In response to this comment, we did a fresh analysis using age at marriage as a count variable. We also have three categories for age at marriage: (i) very early marriage at <15 years’, (ii) ‘marriage at 15-17 years’, and (iii) ‘marriage at age 18+’. The new analysis shows variations in antenatal use and other characteristics between those who had very early marriage at <15 and those who married at 15-17, and 18+. These changes have been reflected in our method section, as well as in analysis and results.

Comments

3. Results:

a. The authors state that age at marriage ‘was significantly associated with the timing of ANC visit and adequacy of ANC use in most countries studied’ – however, this is misleading. Table 2 shows that these findings were significant (p<0.05) for 7 out of 19 countries for early ANC start (i.e., 37% of the sample), and 11 out of 20 for 4+ ANC visits (55% of total sample), which I would not say is ‘most countries’. For initiating ANC visits early, the overall difference across all countries between those married before 18 years and those married at 18+ years is slim (34% vs 38%). There is a bigger difference for those who had 4+ ANC visits, but this too is limited to bivariate analyses.

Response

Thank you for these comments. We have revised the manuscript in line with the suggestions. The results section now has the correct presentation of results.

Comments

b. I think the most interesting findings in this manuscript lie in Table 3. Here, the authors show that girls/women who marry before age 18 and those who marry at 18+ years differ significantly by a number of socio-economic and demographic characteristics: including education, occupation, household wealth index, media exposure, parity and urban/rural residence. This perhaps indicates, and is not reflected in the authors’ discussion at all, that girls who marry earlier are quite different in a number of ways to those who marry later and that these socio-economic and demographic characteristics may perhaps be driving BOTH early marriage as well as ANC use (and as such, that the relationship between age at marriage and ANC use is confounded by these socioeconomic and demographic characteristics). I suggest this is pulled out more in both the Results and Discussion sections.

Response

Thank you for these suggestions. We have considered presenting these important results much more clearly in the results and discussion sections. All changes to the revised manuscript are tracked up.

Comments

c. My comment above is further supported by the authors’ main findings in the regression models. Firstly, education appears to drive the effect between age at marriage and adequate (4+ times) use of ANC. The association is also partially driven by other socio-economic and demographic factors included in the model – or in other words, all these factors are correlated with both age at marriage and adequate ANC use. Secondly, there is no association between age at marriage and timing of ANC use once socio-economic and demographic factors are controlled for. Again, the relationship between age at marriage and timing of ANC use appears to be driven by these socio-economic and demographic factors that are included in the models. These findings need to be brought out substantially in the discussion.

Response

Based on the above suggestions, one of the major findings from this study is that many of the socio-economic and demographic characteristics that influence early marriage are also key drivers of low or inadequate uptake of ANC. These points have been clearly presented in the discussion section.

Comments

4. Discussion:

a. The discussion would be richer if it included details on the variation in age at marriage and ANC use across all SSA countries, instead of generalised statements like ‘almost three-fifths of young women in selected countries married as child brides’ as these can be misleading – which countries are they referring to? Again, it would be a lot more valuable to see variation in age at marriage under 18 years – how many of these women were marrying at age 17 (which is not so different from 18) and how many of them were marrying below that age, and especially how many (and in which countries) are marrying at very young ages (e.g., 13-14).

Response

Thank you for these suggestions. Considering them in the revised manuscript has made the discussion a lot better.

Comments

b. Equally, it would be valuable to examine age at first birth/pregnancy, and how that varies across regions and countries, as that is perhaps more directly related to ANC use than age at marriage.

Response

Age at first pregnancy is not available while age at first birth is only available for a few countries. Meanwhile, age at first marriage, as used in this study, is a good proxy for the two variables because marriage is closely linked to first pregnancy as women in many sub-Saharan African societies are under pressure and are expected to prove their fertility soon after marriage.

Comments

c. A main strength of this paper is that the authors show which socio-economic and demographic characteristics of women are associated with ANC use, and which of these are also associated with early marriage. They in fact find no evidence to support their prediction that early marriage is associated with poor ANC use. However, in their discussion, they choose to present their bivariate findings instead of results from their final models which is misleading. Their recommendations are based on findings which they have themselves stated are not significant (p<0.05, Odds Ratios close to 1, and 95% confidence intervals crossing 1). I suggest this is revised.

Response

Thank you for the comments. We have now revised all sections of the manuscript. The multivariable analysis that was done previously showed an insignificant relationship between age at first marriage and antenatal care use. However, based on reviewers’ suggestions, we have undertaken a fresh analysis where we re-categorised age at first marriage to three groups in order to distinguish between respondents who married at a very early age (<15 years) and those who married at ages 15-17 and 18+. Our fresh analysis also controlled for the country of residence, and the results now show a significant relationship between age at first marriage and the two indicators of antenatal care uptake. The significant relationship between the outcome and exposure variables was as a result of re-categorizing age at first marriage and as well controlling for country of residence. The results demonstrate some between-country variations. We have discussed these findings in our discussion section.

Comments

d. Much of the literature cited in the discussion seems to suggest that poor educational attainment, low SES etc. are all associated with early marriage, but they do not consider that these factors may be what also lead to poor ANC use (e.g., issues of access and information may affect ANC use independent of age at marriage, and this is in fact shown in their regression models.)

Response

The discussion has been revised to demonstrate that poor educational attainment and low socio-economic status are both drivers of early marriage and poor ANC use. We have also highlighted the roles of other factors that independently influence ANC use, such as the issues of information and access to access. These points have been clearly presented in the discussion.

Comments

e. Page 13, first paragraph, last sentence – more detail needed. Each of these factors should be discussed to show how they relate to both age at marriage and ANC use. I also think it is important to include a discourse here on the finding that after controlling for a number of socio-economic and demographic factors, age at marriage was in fact found to have no association with either measure of ANC use; and further that these socio-economic and demographic factors were strongly associated with ANC use and age at marriage. Why do the authors think these socio-economic and demographic factors are associated with both their exposure and outcome variables, and what are the possible pathways for these associations?

Response

The discussion has been revised to carefully reflect all the suggestions. We have presented a detailed discussion on how each of the selected factors relate to both age at marriage and ANC use.

Comments

f. The authors do not give thought to why women might be marrying early and ignore contexts where women may be choosing to marry before age 18 (see Schaffnit, Urassa, Lawson, 2019; Stark, 2018; and others – citations given below). As such, there is some confusion between early marriage and forced marriage – whereas not all marriages before age 18 years are forced, or against the wishes of girls/women. By assuming that marriages before 18 years are forced or against women’s wishes, the authors take autonomy/agency away from these women, and simultaneously consider, for example, women marrying at age 18 (or slightly older) to have full agency, some of whom may not be very different to women aged 17 years and may also be entering marriages against their wishes. Again, important nuance would be added to this paper if the age at marriage variable distinguishes between very young girls and those who are closer to 18 years but still considered as ‘children’, as well as between those in the 18+ category (e.g., between an 18 year old and a 30 year old). I also recommend thinking a bit further about contextual differences in the meaning of ‘childhood’ as the definition of childhood can vary cross-culturally (see Hart, 2006; Rosen, 2007 - citations given below).

Response

The revised manuscript now reflects the distinction between early marriages that are forced and the voluntary ones, thus giving consideration to women autonomy and agency. We have also included additional literature and presented a discussion on the contextual differences regarding the definition of childhood and reasons why young women marry early in different contexts. Also the revised analysis presents a clear distinction between very early marriage (before age 15) and those who married at 15-17.

Comments

g. Further, a conceptual framework outlined in the introduction may help highlight which characteristics of marriage the authors expect will lead to poorer ANC use, distinguishing between, for example, forced marriage (and related loss of autonomy/agency), very early marriage (for example 13- or 14-year-olds), and age at first birth (and other aspects). As it stands, the authors are conflating these concepts under the umbrella of ‘child marriage’ / ‘marriage under 18-years’.

Response

As suggested, a clear conceptual framework is now presented in the literature review section, clarifying the expected relationship between the selected characteristics and the outcome measures.

Comments

Minor comments

1. Terminology: I would suggest using the term ‘age at marriage’ throughout the paper to refer to the main exposure, instead of ‘child/adult marriage’. For example, in the Results section when discussing bivariate analyses, I think the authors mean ‘age at marriage’ was associated with ANC visits, not ‘child marriage’. Here, using the term ‘child marriage’ indicates that only marriage before 18 years is associated with ANC and not marriage at 18+ years – whereas the indicator that the authors are using is actually ‘age at marriage’. Using one term to describe their variable will add consistency to the manuscript.

Response

Based on the suggestions, the revised manuscript now ensures consistency by using same terminology – ‘age at first marriage’ accordingly.

Comments

2. Can this analysis be carried out using a linear variable for age at marriage – what is the effect of very early marriage (e.g., 13-15 year olds) versus 16-17 year olds versus 18-19 year olds? This would help differentiate the effects of very early marriage to marriage at ages closer to 18 years.

Response

In response to this comment, we did a fresh analysis using age at marriage as a count variable. In the descriptive analysis, we also have three categories for age at marriage: (i) very early marriage at <15 years’, (ii) ‘marriage at 15-17 years’, and (iii) ‘marriage at age 18+’. The new analysis shows variations in antenatal use and other characteristics between those who had very early marriage at <15 and those who married at 15-17, and 18+. These changes have been reflected in our method section, as well as in the analysis, results and discussion.

Comments

3. Abstract: The abstract needs to reflect the main findings - i.e., no association between age at marriage and ANC use after controlling for certain socio-economic and demographic variables.

Response

The revised abstract now reflects results from our fresh analysis.

Comments

4. Introduction:

a. What about younger unmarried woman - what is the rationale behind restricting analyses to married women, and why don’t the authors directly explore effects of early childbearing? An explanation can be added to the introduction.

Response

The focus of the present paper is to explore whether child marriage is associated with ANC use. Our new analysis that considered additional variable has shown that there is a relationship between the two variables. Other interesting results also emerged and showed that young women and girls who married earlier than age 18 and those who married at age 18+ differ significantly by several socio-economic and demographic characteristics. We have presented these findings in the discussion section.

Comments

b. The authors state that a high risk of gender-based violence among women married before age 18 would lead to lower ANC use – this may be true, but does not seem relevant to this paper. If it is relevant, the authors should clarify the links between age at marriage, gender-based violence and ANC use and elaborate on this relationship in detail, citing relevant literature.

Response

We have presented a conceptual framework that clarifies the relationship between ANC use and selected characteristics. We did not examine the influence of gender-based violence on ANC use, therefore this variable has been removed from our discussion.

Comments

3. Methods:

a. Clarity needed on the ANC measure for 4+ visits - what time frame does this refer to, the previous/most recent pregnancy?

Response

The ANC grouping of ‘less than 4 visits’ and ‘4+ visit’ is based on the recommendation by the Word Health Organization which stipulates the latter category as a minimum required number of visits to ensure optimal positive maternal health and newborn outcomes. The ANC use relates to the index child (which is the most recent birth). These details have been included in the method section of the revised manuscript.

Comments

4. Discussion:

a. Similar to minor comment 4b above: Stark statements are made about domestic violence and abuse with no clear explanation or rationale about how this relates to ANC use and early marriage – this topic is not explored in the authors' analyses, and these posited associations are not supported with relevant literature. I suggest this is revised either to fully explore how violence against women is associated with both ANC use and early marriage, with relevant citations, or the emphasis on violence against women is minimised as this is not directly relevant to this paper, i.e., the authors do not test the association between violence, ANC use and age at marriage.

Response

More information and elaboration are now provided in the literature and conceptual framework. However, because we did not examine the influence of gender-based violence on ANC use, this variable has been removed from our discussion.

Comments

b. The authors use causal terminology such as ‘child brides may initiate ANC visit late due to poor knowledge about their health issues’ without providing any supporting literature. Some of these statements come across as opinions and/or value judgements – citations are needed here, and even when literature is cited the different contexts of different studies (especially the age of women / age at marriage) need to be highlighted.

Response

Relevant literature is now provided to support the statements made on the hypothesized relationship between ANC use and selected variables.

Comments

5. Papers of potential interest:

Dixon-Mueller, R. (2008). How young is “too young”? Comparative perspectives on adolescent sexual, marital, and reproductive transitions. In Studies in Family Planning (Vol. 39, pp. 247–262). Stud Fam Plann. https://doi.org/10.1111/j.1728-4465.2008.00173.

Hart, J. (2006). Saving children: what role for anthropology?, 1968(1), 131–134.

Rosen, D. M. (2007). Child Soldiers, International Humanitarian Law, and the Globalization of Childhood. American Anthropologist, 109(2), 296–306. https://doi.org/10.1525/aa.2007.109.2.296

Schaffnit, S. B., Hassan, A., Urassa, M., & Lawson, D. W. (2019, February). Parent–offspring conflict unlikely to explain ‘child marriage’ in northwestern Tanzania. Nature Human Behaviour. Nature Publishing Group. https://doi.org/10.1038/s41562-019-0535-4

Schaffnit, S. B., Urassa, M., & Lawson, D. W. (2019). “Child marriage” in context: exploring local attitudes towards early marriage in rural Tanzania. Sexual and Reproductive Health Matters, 27(1), 93–105. https://doi.org/10.1080/09688080.2019.1571304

Stark, L. (2018a). Early marriage and cultural constructions of adulthood in two slums in Dar es Salaam. Culture, Health and Sexuality, 20(8), 888–901. https://doi.org/10.1080/13691058.2017.1390162

Stark, L. (2018b). Poverty, Consent, and Choice in Early Marriage: Ethnographic Perspectives from Urban Tanzania. Marriage and Family Review, 54(6), 565–581. https://doi.org/10.1080/01494929.2017.1403998

Response

Thank you. The suggested papers have been reviewed and relevant ones have been cited accordingly.

________________________________________

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Additional references included in the revised manuscript

Adhikari, R. (2018). Child Marriage and Physical Violence: Results from a Nationally Representative Study in Nepal. Journal of Health Promotion, 6, 49-59.

Al-Eisawi, Z., Jacoub, K., & Alsukker, A. (2021). A large-scale study exploring understanding of the national premarital screening program among Jordanians: Is an at-risk marriage a valid option for Jordanians? Public Understanding of Science, 30(3), 319-330.

Mobolaji, J. W., Fatusi, A. O., & Adedini, S. A. (2020). Ethnicity, religious affiliation and girl-child marriage: a cross-sectional study of nationally representative sample of female adolescents in Nigeria. BMC Public Health, 20, 1-10.

Omariba, D. W. R., & Boyle, M. H. (2007). Family Structure and Child Mortality in Sub-Saharan Africa: Cross-National Effects of Polygyny. Journal of Marriage and Family, 69, 528–543

Schaffnit, S. B., Urassa, M., & Lawson, D. W. (2019). “Child marriage” in context: exploring local attitudes towards early marriage in rural Tanzania. Sexual and reproductive health matters, 27(1), 93-105.

Schaffnit, S. B., Wamoyi, J., Urassa, M., Dardoumpa, M., & Lawson, D. W. (2020). When marriage is the best available option: Perceptions of opportunity and risk in female adolescence in Tanzania. Global public health, 1-14.

Spagnoletti, B. R. M., Bennett, L. R., Kermode, M., & Wilopo, S. A. (2018). ‘I wanted to enjoy our marriage first… but I got pregnant right away’: a qualitative study of family planning understandings and decisions of women in urban Yogyakarta, Indonesia. BMC Pregnancy and Childbirth, 18(1), 353. https://doi.org/10.1186/s12884-018-1991-y

Submitted filename: Response to reviewers_PLOS ONE_25Aug2021.docx

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7 Dec 2021

PONE-D-21-15115R1Comparing the timeliness and adequacy of antenatal care uptake between women who married as child-brides and adult-brides in 20 sub-Saharan African countriesPLOS ONE

Dear Dr. Adedini,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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ACADEMIC EDITOR:Dear authors on your scholarly work; you have brought an important study problem in the area of practice.However, the manuscript has some language usage flaws including punctuations, wordings, spelling and grammar errors. These problems are found throughout the manuscript. Moreover, there are some minor methodological limitations as the reviewer raised. Therefore, please make repeated proof-reading and thorough copyediting before resubmitting the manuscript. This would help increase the readability of the manuscript if published.

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PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

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Reviewer #2: (No Response)

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Reviewer #2: Yes

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Reviewer #2: Yes

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Reviewer #2: Yes

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Reviewer #2: Yes

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6. Review Comments to the Author

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Reviewer #2: The authors have done a good job in addressing the previous round of reviewer comments and the manuscript reads well now. Thank you for your detailed responses to my comments, much appreciated!

A few minor comments:

1. In the response to reviewer comments, you mentioned that data on age at first pregnancy is not available in the DHS and age at first birth was available for very few countries. I would add this point to your methods section too. You have added the point about why you used age at first marriage from a theoretical perspective but this will also clarify why you had to do this from a practical perspective.

2. Your conclusion states that from a policy perspective, ending early marriage is the solution to improving ANC use. Agreed, these two concepts are related, but perhaps also consider the idea that improving girls/women's socio-economic wellbeing, which - as acknowledged clearly in your discussion now - is a driver of both ANC use and age at marriage, should perhaps be the key focus of policy makers/programmes?

3. Table 2 - typo in heading: 'parentage' instead of 'percentage'

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Reviewer #2: No

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13 Dec 2021

Response to Editor’s and reviewer’s comments

==============================

ACADEMIC EDITOR:

Comments

Dear authors on your scholarly work; you have brought an important study problem in the area of practice. However, the manuscript has some language usage flaws including punctuations, wordings, spelling and grammar errors. These problems are found throughout the manuscript. Moreover, there are some minor methodological limitations as the reviewer raised. Therefore, please make repeated proof-reading and thorough copyediting before resubmitting the manuscript. This would help increase the readability of the manuscript if published.

Response

Thank you for the comments. We have done a thorough editing of the manuscript and addressed the problems on punctuations, spelling and grammar errors. We have also addressed the minor methodological issues raised.

Reviewers' comments:

Reviewer #2: The authors have done a good job in addressing the previous round of reviewer comments and the manuscript reads well now. Thank you for your detailed responses to my comments, much appreciated!

Response

Thank you.

Comments

A few minor comments:

1. In the response to reviewer comments, you mentioned that data on age at first pregnancy is not available in the DHS and age at first birth was available for very few countries. I would add this point to your methods section too. You have added the point about why you used age at first marriage from a theoretical perspective but this will also clarify why you had to do this from a practical perspective.

Response

As advised, we have included the suggested information in the methods section of the manuscript as shown below:

We could not use variables such as age at first pregnancy and age at first birth because the former is not available in the DHS while the latter is only available for a few countries.

Comments

2. Your conclusion states that from a policy perspective, ending early marriage is the solution to improving ANC use. Agreed, these two concepts are related, but perhaps also consider the idea that improving girls/women's socio-economic wellbeing, which - as acknowledged clearly in your discussion now - is a driver of both ANC use and age at marriage, should perhaps be the key focus of policy makers/programmes?

Response

Thank you for the suggestion. We have included the additional recommendation in the manuscript as shown below:

Besides, considering the precarious conditions of child brides, including low education, poor employment prospects and generally low socio-economic status, interventions to improve the situations of girl-children must be a major focus and consideration of policymakers.

Comments

3. Table 2 - typo in heading: 'parentage' instead of 'percentage'

Response

We have changed ‘parentage’ to ‘percentage’

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

3 Jan 2022

Comparing the timeliness and adequacy of antenatal care uptake between women who married as child-brides and adult-brides in 20 sub-Saharan African countries

PONE-D-21-15115R2

Dear Dr. Sunday A. Adedini,

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Kind regards,

Wubet Alebachew Bayih, M.Sc.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

6 Jan 2022

PONE-D-21-15115R2

Comparing the timeliness and adequacy of antenatal care uptake between women who married as child brides and adult brides in 20 sub-Saharan African countries

Dear Dr. Adedini:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

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on behalf of

Dr. Wubet Alebachew Bayih

Academic Editor

PLOS ONE