Spatial distribution and determinants of abortion among reproductive age women in Ethiopia, evidence from Ethiopian Demographic and Health Survey 2016 data: Spatial and mixed-effect analysis.

BACKGROUND: Unsafe abortion remains a global public health concern and it is the leading cause of maternal mortality and morbidity. Despite the efforts made to improve maternal health care service utilization, unsafe abortion yet constitutes the highest maternal mortality in Sub-Saharan Africa (SSA) including Ethiopia. Although abortion among reproductive-age women is a common problem in Ethiopia, there is limited evidence about the spatial distribution and determinants of abortion. Therefore, this study aimed to investigate the spatial distribution and determinants of abortion among reproductive-age women in Ethiopia.
METHODS: A secondary data analysis was conducted using the 2016 Ethiopian Demographic and Health Survey (EDHS) data. A total of 12378 reproductive-age women were included in this study. The Bernoulli model was fitted using SaTScan version 9.6 statistical software to identify significant hotspot areas of abortion and ArcGIS version 10.6 statistical software was used to explore the spatial distributions of abortion. For the determinant factors, a mixed effect logistic regression model was fitted to take into account the hierarchical nature of the EDHS data. Deviance (-2LL), AIC, BIC, and ICC were used for model comparison. The AOR with a 95% CI was estimated for the potential determinants of abortion.
RESULTS: The overall prevalence of abortion in Ethiopia was 8.9% ranging from 4.5% in Benishangul to 11.3% in Tigray regions. The spatial analysis revealed that abortion was significantly varied across the country. The SaTScan analysis identified a total of 60 significant clusters, of these 19 clusters were primary clusters. The primary clusters were located in the northern part of the Tigray region (LLR = 26.6, p<0.01; RR = 2.63). In the multivariable mixed-effect logistic regression analysis; primary education [AOR = 1.36; 95% CI: 1.13, 1.64], rural residence [AOR = 4.96; 95% CI: 3.42, 7.18], protestant religion follower [AOR = 0.56; 95% CI: 0.42, 0.75], richest wealth status [AOR = 1.72; 95% CI: 1.24, 2.40], maternal age 45-49 years [AOR = 3.12; 95% CI: 1.52, 6.44], listening radio [AOR = 1.27; 1.01, 1.60], and watching television [AOR = 1.45; 1.04, 2.01] were significant determinants of abortion.
CONCLUSIONS: The prevalence of abortion remains unacceptably high in Ethiopia. The spatial distribution of abortion has been significantly varied across regions in Ethiopia. Having primary education, being rural, having media exposure, and being from the richest household were significantly associated with higher odds of abortion whereas being protestant religious followers were associated with lower odds of abortion. Therefore, the government should design public health programs targeting the identified hotspot areas of abortion and should scale up maternal health programs in rural areas, to reduce maternal morbidity and mortality.

Background

Abortion is defined as the loss of product of conception (whether induced or spontaneous) before 28 completed weeks of gestation [1, 2]. Globally, an estimated 55.9 million unsafe abortions occur annually, of these 49.3 million were occurred in developing countries [3]. Unsafe abortion is the leading cause of maternal mortality and morbidity [4]. It accounts for 13% of global maternal mortality [5] and 5 million disabilities annually [6, 7]. The majority of unsafe abortion can be prevented through education on sexual behavior, family planning, and the provision of safe abortion [8].

Unsafe abortion is a major public health concern [3], particularly in developing countries where unintended pregnancies are common due to ineffective use or nonuse of contraceptives [9]. The magnitude of unsafe abortion has varied across countries, ranging from 3.1% in western Africa to 3.8% in northern Africa [10, 11]. Even though unsafe abortion is reduced in developed nations where the liberalization of abortion law and safe abortion service is legally available [12, 13], it remains high in developing countries particularly in Sub-Saharan Africa (SSA) where abortion is legally restricted [14-16].

Prior studies have documented that unsafe abortion has been an important and ongoing health problem in Ethiopia. In 2008, an estimated 382,000 induced abortions were performed in Ethiopia with a prevalence of 13% [6], mainly related to unwanted pregnancies [17]. According to the Ethiopian Demographic and Health Survey (EDHS) 2016 report, the maternal mortality rate was 412 per 100,000 births [18].

Previous studies done on abortion revealed that residence, parity, educational status, antenatal care (ANC) utilization, place of delivery, maternal nutritional status, and maternal obstetric factors were significantly associated with abortion [19-21]. The prevalence of abortion has been varied not only among countries but also within the country [22] and it is highly concentrated among rural residents, poor and marginalized societies [23, 24]. Thus, exploring the spatial distributions of abortion has become fundamental to design evidence-based public health interventions [25].

Though there are studies conducted on the determinants of abortion in Ethiopia [26], information is scant on the spatial distribution and its determinant factors at the national level. Therefore, we aimed to investigate the spatial distribution and determinants of abortion among reproductive-age women in Ethiopia. As abortion and abortion-related mortality is an indicator of availability and quality of maternal health services [27], understanding the significant hotspot areas of abortion would help to evaluate the quality of service and access to maternal health services. Furthermore, the findings of this study could guide policymakers in designing effective public health interventions to reduce abortion and abortion-related maternal morbidity and mortality.

Method and materials

Study design, setting and period

Secondary data analysis was conducted based on the 2016 EDHS data. The EDHS is a nationally representative survey conducted in every five years in the nine regional states (Afar, Amhara, Benishangul-Gumuz, Gambela, Harari, Oromia, Somali, Southern Nations, Nationalities, and People's Region (SNNPR), and Tigray), and two administrative cities (Addis Ababa and Dire-Dawa) of Ethiopia [28]. In 2016, the total population of Ethiopia was 102 million, of these 43.47% were aged less than 14 years. Around 35 million Ethiopian people are living in poverty/had low socioeconomic status. The crude birth rate in Ethiopia is 36.5 per 1000 populations with a total fertility rate of 4.46. Ethiopia has a three-tire health system; primary health care unit (Primary hospital, health center, health post, primary clinic, and medium clinic), secondary health care (General hospital, specialty clinics, and specialty centers), and tertiary health care (Specialized hospital). The number of hospitals, in general, health facilities, varies from region to region [29].

Source and sample population

The source population was all pregnant women within five years before the survey in Ethiopia, while all pregnant women in the selected enumeration areas within five years before the survey were the study population. In EDHS, a stratified two-stage cluster sampling technique was employed using the 2007 Population and Housing Census as a sampling frame. In the first stage, 645 enumeration areas (EAs) were selected with probability proportional to the EA size and with independent selection in each sampling stratum. In the second stage, on average 28 households were systematically selected. A total weighted sample of 12378 reproductive-age women was included in this study. The detailed sampling procedure exists in the full EDHS 2016 report [30].

Variables and data collection procedure

The dependent variable for this study was “abortion”, which was derived from the EDHS question “have you ever had a terminated pregnancy”. The outcome variable was dichotomized as “Yes” if a woman had experienced abortion, and “No” if a woman didn't experience abortion within the study period. The independent variables included in the study were maternal age, residence, educational status, marital status, religion, frequency of watching television, frequency of listening radio, wealth status, and birth history.

The data were accessed from the DHS program official database www.measuredhs.com, after permission was granted through an online request by explaining the objective of the study. We used the EDHS 2016 birth data (BR) set. The geographic coordinate data (longitude and latitude coordinates) was taken at the cluster/ enumeration area level after we explain the purpose of conducting the spatial distribution of abortion.

Data management and analysis

The data were weighted using sampling weight, primary sampling unit, and strata before any statistical analysis to restore the representativeness of the survey and to take into account the sampling design and get reliable statistical estimates.

Spatial analysis

ArcGIS version 10.6 and SaTScan version 9.6 statistical software were used for exploring the spatial distribution, global spatial autocorrelation, spatial interpolation, and for identifying significant hotspot areas of abortion.

Spatial autocorrelation analysis. The spatial autocorrelation (Global Moran’s I) is the correlation coefficient for the relationship between a variable and its surrounding value, it measures the overall spatial autocorrelation of abortion [31]. Moran's I is a spatial statistics used to measure spatial autocorrelation by taking the entire data set and produce a single output. The spatial autocorrelation coefficient is statistically significant when tested against the null hypothesis that the observed value differs with its expected value which is -1/ (n-1), where n is the number of points at enumeration area level for which the autocorrelation is being computed. Moran’s I value ranges from-1 to 1 [32]. A value close to 1 shows a strong positive spatial autocorrelation whereas a value close to -1 shows a strong negative spatial autocorrelation. If Moran’s I close to 0, it indicates that there is no spatial autocorrelation. A statistically significant Moran's I value (p < 0.05) can lead to rejection of the null hypothesis (abortion is randomly distributed) and indicates the presence of spatial autocorrelation.

Spatial interpolation. The spatial interpolation technique was used to predict abortion on the un-sampled areas in Ethiopia based on sampled measurements. There are various deterministic and geostatistical interpolation methods. Among the interpolation techniques, ordinary Kriging and empirical Bayesian Kriging are the best interpolation methods since they optimize the weight [33]. Kriging spatial interpolation method was used in this study for predicting abortion in unobserved areas since it had a small mean square error and residual. It produces smooth maps of abortion by predicting the prevalence of abortion on the un-sampled locations (enumeration areas) and it is an optimal interpolation based on regression against observed values of the surrounding data points, and weighted according to the spatial covariance values.

Spatial scan statistical analysis. In the spatial scan statistical analysis, Bernoulli based model was employed to identify statistically significant spatial clusters of abortion using Kuldorff’s SaTScan version 9.6 software. For this study, we used a circular scanning window that moves across the study area since the elliptical window is inactive in the SaTScan software. Women who experienced abortion were taken as cases and those who didn’t experience abortion were considered as controls to fit the Bernoulli model. The numbers of cases in each location had Bernoulli distribution and the model required data for cases, controls, and geographic coordinates. The default maximum spatial cluster size of <50% of the population was used, as an upper limit, since it allowed both small and large clusters to be detected and ignored clusters that contained more than the maximum limit. Selecting the cluster size of 50% of the total population is the default option for the maximum scanning window size and it is often used to search the most likely clusters with a higher value of the likelihood value. Kuldorff's indicated that a window-sized up to 50% of the population at risk can reduce negative clusters (highly sensitive), avoid missing clusters, and more likely to contain the true significant clusters than the small scanning window.

For each potential cluster, a Likelihood Ratio (LR) test statistic and the p-value was used to determine if the number of observed abortion cases within the potential cluster was significantly higher than expected or not. The scanning window with maximum likelihood was the most likely performing cluster, and the p-value was assigned to each cluster using Monte Carlo hypothesis testing by comparing the rank of the maximum likelihood from the real data with the maximum likelihood from the random datasets. The primary and secondary clusters were identified and assigned p-values and ranked based on their likelihood ratio test, based on 999 Monte Carlo replications [34].

Mixed effect logistic regression analysis

Cross tabulations and summary statistics were done using STATA version 14 software. The EDHS data has hierarchical nature; hence women are nested within a cluster and we expect that women within the same cluster may be more similar to each other than women in another cluster. This violates the assumption of the traditional regression model which is the independence of observations and equal variance across clusters. Therefore, an advanced statistical model is needed to take into account the between cluster variability to get a reliable standard error and unbiased estimate. Besides, since the outcome variable was binary standard logistic regression and Generalized Linear Mixed Models (GLMM) were fitted and model comparison, as well as model fitness, was done based on the Intra-Class Correlation Coefficient (ICC), Akaike Information Criteria (AIC), Bayesian Information Criteria (BIC), and Deviance values. The mixed-effect logistic regression model was the best-fitted model since it has the lowest deviance and variables with p-value <0.20 in the bi-variable analysis were considered for the multivariable mixed-effect logistic regression model. Finally, Adjusted Odds Ratio (AOR) with 95% Confidence Interval (CI) were reported and those variables with p-value <0.05 were declared to be significant factors associated with abortion. In the bi-variable mixed-effect binary logistic regression analysis; maternal age, religion, residence, wealth status, educational status, frequency of watching television, frequency of listening radio, birth history, and marital status had a p-value< 0.2 and were considered for multivariable analysis.

However, in the multivariable analysis; educational status, residence, maternal age, frequency of watching television, frequency of listening radio, and religion were significantly associated with abortion.

Ethics consideration

Since the study was a secondary data analysis of publically available survey data from the MEASURE DHS program, ethical approval and participant consent were not necessary for this particular study. We requested DHS Program and permission was granted to download and use the data for this study from http://www.dhsprogram.com. The Institution Review Board approved procedures for DHS public-use datasets do not in any way allow respondents, households, or sample communities to be identified. There were no names of individuals or household addresses in the data file. The geographic identifiers only go down to the regional level (where regions are typically very large geographical areas encompassing several states/provinces). Each enumeration area (Primary Sampling Unit) has a PSU number in the data file, but the PSU numbers do not have any labels to indicate their names or locations. In surveys that collect GIS coordinates in the field, the coordinates are only for the enumeration area (EA) as a whole, and not for individual households, and the measured coordinates are randomly displaced within a large geographic area so that specific enumeration areas cannot be identified.

Result

Socio-demographic characteristics of respondents

A total of 12378 women was included in this study. Of these, 89% were rural residents, and 44.1% were lived in the Oromia region. The majority (66.8%) of women had no formal education and about 93.7% of respondents were married. The median age of respondents was 29 (IQR± 9) years (Table 1).

Table 1

Socio-demographic characteristics of respondents in Ethiopia, 2016 (N = 12378).

Variables	Percent (%)
Residence
Urban	11.0
Rural	89.0
Region
Tigray	6.4
Afar	1.1
Amhara	18.6
Oromia	44.1
Somali	4.7
Ben-Gumuz	1.1
Gambela	21.0
Harari	0.2
Addis Ababa	2.1
Dire Dawa	0.4
Maternal age (in years)
15–19	3.0
20–24	18.0
25–29	30.2
30–34	23.2
35–39	16.2
40–44	7.0
45–49	2.4
Maternal educational status
No education	66.8
Primary	26.3
Secondary	4.5
Higher	2.4
Religion
Orthodox	34.0
Muslim	41.2
Catholic	0.9
Protestant	21.5
Others*	2.4
Husband education
No education	45.9
Primary	36.9
Secondary	7.0
Higher	10.2
Marital status
Never married	0.5
Married	93.7
Living with a partner	1.1
Widowed	1.2
Divorced	2.5
Separated	1.0

Keys:

* = Traditional religious follower.

Obstetric and socioeconomic characteristics of respondents

Nearly half (44.4%) of the respondents had ≥ 4 births, and 23.9% of women were from the poorest household. Concerning listening radio, about 73.6% of respondents had never listened to the radio (Table 2).

Table 2

Obstetric and socio-economic characteristics of participants in Ethiopia (N = 12378), 2016.

Variables (N = 12378)	Percentage (%)
Wealth status
Poorest	23.9
Poor	22.6
Middle	20.7
Richer	18.4
Richest	14.3
Frequency of listening to the radio
Not at all	73.6
Less than once a week	13.2
At least once a week	13.3
Frequency of watching the television
Not at all	82.1
least than once a week	10.0
At least once a week	7.9
Occupational status
Unemployed	70.6
Employed	29.4
Birth history
No birth	12.0
One birth	15.3
Two births	15.1
Three births	13.2
Four and above births	44.4
Preceding birth interval
Less than 24 months	23.4
≥ 24 months	76.6
Terminated pregnancy (abortion)
No	91.1
Yes	8.9
Smoking status
Yes	99.2
No	0.8

Prevalence of abortion among women in Ethiopia, 2016

The overall prevalence of abortion was 8.9% [95%CI: 8.4%-9.5%] ranging from 4.5% in Benishangul-Gumuz to 11.3% in Tigray regions (Fig 1). The prevalence of abortion among rural residents was 9.2%, whereas the prevalence of abortion among urban residents was 6.7%.

Fig 1

Regional prevalence of abortion among reproductive-age women in Ethiopia, 2016.

Spatial distribution of abortion

The spatial distribution of abortion showed significant spatial variation across the country with Global Moran's I value of 0.06 (p<0.001). Each point on the map represents one census enumeration area which encompasses several abortion cases. The red color indicates areas with a high prevalence of abortion, whereas the green color indicates areas with a low prevalence of abortion. In this study, the high prevalence of abortion was found in Central and Northern Tigray, Western part of Afar, Eastern part of Benishangul-Gumuz, and Southeast of SNNPRs. The low prevalence of abortion was found in the Gambela region, Western Benishangul-Gumuz, central Oromia, Harari, and Dire Dawa (Fig 2).

Fig 2

The spatial distribution of abortion in Ethiopia, 2016 (source: CSA, 2013).

Kriging interpolation of abortion

Based on EDHS 2016 sampled data, the Kriging interpolation predict the highest prevalence of abortion in Northern Tigray, Addis Ababa, Southwest Oromia, Southwest SNNPRs, and Northern Afar regions. In contrast, the relatively low prevalence of abortion was detected in Gambella, Southern part of Amhara, Western part of Benishangul-Gumuz, and Eastern part of Afar regions (Fig 3).

Fig 3

The Kriging interpolation of abortion in Ethiopia, 2016 (source: CSA, 2013).

Spatial scan statistical analysis

A spatial scan statistical analysis identified a total of 60 significant primary and secondary clusters. Of these 19 clusters were primary (most likely) clusters which were located in the Northern Tigray region centered at 14.175601 N, 38.891649 E with 62.42 km radius, a Relative Risk (RR) of 2.63, and Log-Likelihood Ratio (LRR) of 26.6, at p-value<0.01. It revealed that pregnant women within the spatial window had 2.63 times higher risk of experiencing abortion as compared to pregnant women outside the spatial window (Table 3). The secondary clusters were located in border areas of Oromia and Amhara regions, southeastern Oromia, and border areas between SNNPRs and Oromia regions. The bright red color circular window (Rings) indicates statistically significant spatial windows containing a high prevalence of abortion (Fig 4).

Table 3

Significant spatial clusters of abortion among women in Ethiopia, 2016.

Clusters	Enumeration areas (EAs)/ clusters detected	Coordinates/radius	Population	Cases	RR	LLR	P-value
1	84, 45, 81, 590, 481, 461, 400, 636, 597, 89, 479, 604, 156, 355, 598, 584, 404, 226, 579	(14.175601 N, 38.891649 E) / 62.42 km	327	70	2.63	26.6	<0.001
2	452, 472, 286, 289, 123	(7.410925 N, 40.475707 E) / 85.79 km	125	27	2.58	10.2	0.01
3	92	(6.708449 N, 44.273542 E) / 0 km	34	12	4.19	9.5	0.03
4	510, 267, 572, 10, 423, 350, 229, 482, 460, 206, 176, 531, 218, 310, 617, 120, 637, 517, 112, 201, 274, 463, 144, 464, 532, 91, 369, 170, 11, 153, 287, 339, 626, 107, 247	(10.160658 N, 38.634847 E) / 125.60 km	412	61	1.79	9.2	0.04
5	50, 342, 86, 21, 503, 450, 574, 182, 505, 398	(5.546952 N, 37.666334 E) / 88.77 km	267	42	1.89	7.5	0.171
6	276	(10.717422 N, 40.344525 E) / 0 km	25	9	4.26	7.3	0.218
7	564, 39, 230, 51	(9.555410 N, 40.326165 E) / 34.04 km	61	15	2.92	7.08	0.245

Fig 4

The SaTScan analysis of hotspot areas of abortion in Ethiopia, 2016 (source: CSA, 2013).

Determinants of abortion among reproductive-age women in Ethiopia

Model comparison

AIC, BIC, and deviance were checked and reported as a model comparison parameter. Since the models were nested models we preferred deviance value for model comparison and the mixed effect logistic regression model was the best-fitted model because of the smallest value of deviance (Table 4). Furthermore, the ICC value which was 0.21 and the Log-likelihood ratio test which was (X2 = 238.49, p-value <0.001) informed us to choose a mixed-effect logistic regression model (GLMM) over the basic model.

Table 4

Model comparison between standard logistic regression and mixed-effects logistic regression.

Model comparison	AIC	BIC	Deviance
Logistic regression model	6856.17	7077.95	6796.09
Mixed effect logistic regression model	6622.02	6851.19	6560.02

In the multivariable mixed-effect logistic regression model; educational status, maternal age, frequency of watching television, residence, frequency of listening radio, and religion were significantly associated with abortion.

The odds of experiencing abortion among women residing in the rural area were nearly 5 times [AOR = 4.96, 95% CI: 3.42, 7.18] higher than those residing in urban areas. The odds of experiencing abortion among women who were protestant religious followers were decreased by 44% [AOR = 0.56, 95% CI: 0.42, 0.75] as compared to Orthodox Christians. The odds of experiencing abortion among women aged 24–29, 30–34, 35–39, 40–44 and 45–49 years were 2.2 times [AOR = 2.20, 95% CI: 1.27, 3.80], 3.2 times [AOR = 3.2, 95% CI: 1.82, 5.71], 3.01 times [AOR = 3.01, 95% CI: 1.67, 5.42], 4.57 times [AOR = 4.57, 95% CI: 2.47, 8.46], and 3.12 times [AOR = 3.12, 95% CI: 1.52, 6.44] higher than those women aged 15–19 years respectively. Women who attained primary education had 1.36 times [AOR = 1.36, 95% CI: 1.13, 1.64] higher odds of experiencing abortion than women who had no formal education. Women from the richest household had 1.72 times [AOR = 1.72, 95% CI: 1.24, 2.40] higher odds of experiencing abortion than women from the poorest household. Media exposure was significantly associated with abortion. The odds of having abortions among women who listened to the radio less than once a week were 1.27 times (AOR = 1.27, CI: 1.01, 1.60) higher than women who never listened to the radio. Women who watched television at least once a week had1.45 times [AOR = 1.45, 95% CI: 1.04, 2.01] higher odds of abortion as compared to women who never watched the television (Table 5).

Table 5

Multivariable mixed-effect logistic regression analysis for assessing determinants of abortion among reproductive age women in Ethiopia, 2016.

Variable	Abortion		AOR (95% CI)
	No	Yes
Residence
Urban	1,983	130	1
Rural	8,989	897	4.96 (3.42, 7.18) **
Age
15–19	390	18	1
20–24	2,211	124	1.27 (0.74, 2.19)
25–29	3,280	282	2.20 (1.27, 3.80) **
30–34	2,443	279	3.23 (1.82, 5.71) **
35–39	1,758	192	3.01 (1.67, 5.42) **
40–44	670	107	4.57 (2.47, 8.46) **
45–49	220	25	3.12 (1.52, 6.44) **
Wealth status
Poorest	4,166	387	1
Poorer	1,848	149	0.85 (0.67, 1.07)
Middle	1,490	154	1.07 (0.84, 1.36)
Richer	1,361	128	0.91 (0.70, 1.19)
Richest	2,107	209	1.72 (1.24, 2.40) *
Educational status
No education	7,158	670	1
Primary	2,688	269	1.36 (1.13, 1.64) **
Secondary	740	55	0.98 (0.68, 1.41)
Higher	386	33	0.99(0.62, 1.61)
Religion
Orthodox	3,083	354	1
Muslim	5,647	518	0.81 (0.64, 1.01)
catholic	75	3	0.40 (0.12, 1.39)
Protestant	1,981	136	0.56 (0.42, 0.75) **
Others	186	16	0.66(0.34, 1.26)
Frequency of listening to the radio
Not at all	8,456	733	1
Less than once a week	1,265	147	1.27 (1.01, 1.60) *
At least once a week	1,251	147	1.21 (0.96, 1.55)
Frequency of watching television
Not at all	8,754	791	1
Less than once a week	877	102	1.25 (0.95, 1.65)
At least once a week	1,341	134	1.45 (1.04, 2.01) *
Birth history
zero birth	1,416	96	1
One birth	1,822	142	0.97 (0.72, 1.31)
Two births	1,649	146	0.92(0.66, 1.27)
Three births	1,514	130	0.85 (0.60, 1.19)
Four and above births	4,571	513	0.85 (0.60, 1.19)
Marital status
Married	10,191	967	1
Never married	273	28	1.22 (0.78, 1.90)
Widowed	158	8	0.52 (0.24, 1.11)
Divorced	349	24	0.78 (0.49, 1.23)

* = p-value<0.05,

** = p-value<0.01,

AOR: Adjusted Odds Ratio; CI: Confidence Interval.

Discussion

Abortion is a major public health problem in Ethiopia [35]. This study was aimed to investigate the spatial distribution and determinants of abortion in Ethiopia. The spatial analysis result revealed that the spatial distribution of abortion was significantly varied across the country. In multivariable mixed-effect logistic regression analysis; wealth status, residence, maternal education, religion, media exposure, and maternal age were significant predictors of abortion.

The current prevalence of abortion was consistent with a study reported in Mozambique [36] and lower than studies conducted in Ghana [36] and northwest Ethiopia [37]. The possible explanation might be due to the difference in the study period, study population used for the study and improvement of maternal health care service accessibility and utilization over time. But the finding of our study was found to be higher than those of studies done in India (1.7%) [38] and Wolaiytasodo- Ethiopia [39]. The difference might be due to the difference in the study population. That is the current study was conducted at the national level (community-based) based on EDHS 2016 while the study in Wolaiytasodo Ethiopia was conducted among university students (institution-based) with a small sample size.

The spatial analysis result revealed that the spatial distribution of abortion was significantly varied across the country, where significant hotspot areas of abortion were identified in the northern Tigray region, border areas of Oromia, Amhara, and SNNP regions. The spatial variation might be related to the difference in socioeconomic status, and health inequality within the country. Besides, this could be attributed to the disparity in the distribution of maternal health service, and the inaccessibility of infrastructure in the border areas and the gap in health service utilization like family planning, ANC and other reproductive health services across regions [40].

In the mixed-effect logistic regression analysis, place of residence was significantly associated with abortion. Women residing in rural areas were more likely to experience abortion as compared to urban residents. It was consistent with study findings in northwest Ethiopia [37] and India [38]. This could be due to lack of access to maternal health care services utilization (such as family planning, ANC visit, awareness about danger signs of pregnancy, and birth preparedness), and limited information about complications of abortion due to lack of access to media in the rural areas [41].

Maternal age was found to be significantly associated with abortion. Women in the age group 25–29, 30–34, 35–39, 40–44, and 45–49 years were more likely to experience abortion than women in the age group of 15–19 years. This was consistent with the study findings reported in Ghana [36], Denmark [42], and Mozambique [36]. The possible explanation could be because older women are more likely to have medical and pregnancy-related complications like high blood pressure (HTN), Diabetic Mellitus (DM), cervical incompetence, cardiovascular diseases and chromosomal abnormality that could complicate the pregnancy and increase the risk of poor pregnancy outcome like abortion [43]. Moreover, as maternal age increase, the risk of chromosomal abnormality will be increased and uterine and hormonal function will be decreased, which finally result in miscarriage/abortion if women become pregnant at an older age [44].

Our study revealed that media exposure was a significant predictor associated with increased odds of abortion. This result agrees with reports in Ghana and Mozambique [36]. The possible reason might be due to media is an important mechanism in providing information about how and where to terminate a pregnancy. Furthermore, women who have media exposure might be aware of available laws related to abortion and less likely to be stigmatized by society [45].

The odds of abortion among protestant religious followers were lower compared to Orthodox Christians. It was consistent with a study finding in China [46] and the possible explanation could be due to lack of access to reproductive health services, and deep-rooted cultural belief towards abortion in the community [46]. Regarding wealth status, in this study, women from the richest household had higher odds of experiencing abortion than those from the poorest household. This finding was consistent with studies in Ghana [47] and Nepal [48]. This might be due to the reason that the wealth status of women can determine their ability to cover the cost of maternal health care services. Besides, poor women are facing cost barriers like transportation costs since the abortion services did not perform elsewhere, this can impede women to have an abortion.

In this study, maternal education was a significant predictor of abortion. Women who had attained primary education had higher odds of abortion as compared to women who had no formal education. This was in line with study findings reported in northwest Ethiopia [37], and India [38]. It could be due to the reason that educated women didn't need to have birth to meet the demands of ongoing education [49]. Besides, educated women might have information and access to abortion services [50].

This study has both strengths and limitations. Since the study used nationally representative data, the findings of the study can be generalized at the national level. Besides, the study was based on an advanced (appropriate) model, by taking into account the clustering effect, to get reliable standard error and estimate. However, due to the cross-sectional nature of the data, the temporal relationship can't be established. Besides, since the outcome was sensitive and collected based on self-reporting, there may be a possibility of social desirability bias that can lead to under-reporting.

Conclusion

This study showed that the spatial distribution of abortion was significantly varied across the country. The hotspot areas of abortion were located in the northern Tigray region, border areas of Oromia, SNNPR, and Amhara region. Besides, maternal age, maternal education, wealth status, media exposure, religion, and residence were significantly associated with abortion. Therefore, policymakers and governmental and non-governmental organizations could strengthen the effort towards reproductive health services particularly for rural residents and should design effective public health interventions in the identified hotspot areas to reduce the incidence of abortion and abortion-related morbidity and mortality. Besides, we recommend scholars to examine the reason why abortion had significant geographic variation within the countries using a detailed exploration like qualitative study.

2 Jan 2020

PONE-D-19-30532

Spatial distribution and determinants of abortion among reproductive-age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey (EDHS) 2016 data: Spatial and Mixed-effect analysis

PLOS ONE

Dear Mr Tesema,

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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Agricola Odoi, BVM, MSc, PhD, FAHA, FACE

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Yes

Reviewer #4: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

Reviewer #3: Yes

Reviewer #4: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

Reviewer #4: No

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Generally, this is an interesting manuscript using epidemiological modelling and spatial epidemiology explore the complex subject of abortion in a developing country. This could inform reproductive health services delivery and other unmet needs in family planing in Ethiopia. It would also be of interest to epidemiologist interested in critiquing epidemiological modelling as a couple of methods are explored. The manuscript could be improved by a further read by english proficient person to sort out grammar and spelling issues and flow. Figures need to be redone to publication quality and also consulting a reproductive health expert in Ethiopia to review this manuscript before resubmission would be useful.

In addition, see comments below

In the Abstract,

1. Statistics in the result section could be summarised better, eg not over repeating 95% CI, only present the most important and interesting results eg you don’t have to put all the statistics for all the age groups,

2. Some repetitions in the conclusions

Line 88, what do you mean by wide gap in abortions

Revise some sentences

Line 113 missing full stop

Line 121, do you mean sample size

Statistics, I think one appropriate method of model evaluations and evaluations could be chosen and be used

Line 245-249, two sentences all talking about high prevalence, which regions do you really refer to as high prevalence

Figures are of poor quality, can be improved to publication quality.

Reviewer #2: This manuscript needs several major changes.

First, a thorough grammatical editing is necessary, as the very first sentence has a spelling error ( uretro)

Secondly, the figures are not helping your analysis. Figure 1 is virtually illegible, Figure 2 needs to be a map at the regional level, with correctly capitalized region/state names. Furthermore, Figure 3 needs help, the points are far too small for the reader to understand anything about the spatial variation in the rate, Figure 4 can be eliminated as the moran I statistic can be reported in the text. Adjust the number of decimal places on the maps, there are too many decimal values, you should report at most 2 decimal places.

Regarding your statistical model, it's more common to model the spatial variation using a CAR random effect in the binomial model, and visualize the random effect or the smoothed rate map, versus doing separate kriging or scan statistic methods. Why bother reporting the un-adjusted odd ratios? THis seems pointless to me, as you end up adjusting them anyway. LIkewise, you do not need to report the weighted n in your table 1, just the %'s

Finally, you need to specify a hypothesis, there are no real research questions or testable hypotheses specified.

Reviewer #3: This is an interesting and well written paper documenting clustering of abortion in Ethiopia. The importance of the topic is well framed in the introduction, and the investigators use appropriate methods to draw conclusions.

My only suggestion is that the manuscript receive another read through to make minor edits to sentence structure for clarity.

Reviewer #4: The authors present an interesting examination of the spatial distribution of abortion in Ethiopia using demographic and health survey data. The methods are appropriately used, with one question about whether the residuals were spatially autocorrelated in the model.

1. Lines 25-27, line 63, line 65, line 67, line 69 and throughout. The authors should specify that “unsafe abortion” rather than “abortion” is a major cause of maternal mortality and a public health concern. Right now the two concepts are conflated.

2. Line 33, line 36. Can the authors define abortion in this population? Is this the percentage of women interviewed who ever had an abortion? Or the percentage of previous pregnancies that ended in abortion?

3. Throughout the authors talk about the rate of abortion and the prevalence of abortion. The authors need to define each, which I believe will have different meanings and interpretations. Are these prevalence of women ever having an abortion, prevalence of pregnancies ending in abortion, or what?

4. The authors should limit significant digits on figure 3. 0-5%, 5-15%, 15-28%, 28-50%.

5. The authors did not present the results from the global moran’s I of the residuals of their regression model. Was this non-significant, indicating that the model explained the spatial variance in the outcome? Or did the authors need to adjust their approach to account for spatially correlated data?

6. For figure 5, I presume this is the LISA? Please indicate

7. The authors should limit significant digits on Figure 6 in a same manner as comment 4.

8. For figure seven I suggest using a single color for their hot spots identified (presuming these are all hotspots). They’re all significant.

9. I didn’t see a good subsection in the methods on the variables considered for the regression model. This needs to be better explained. In the table there was no urban/rural, which I would expect to be a significant factor.

10. I think the authors would benefit from a copyeditor for the English.

**********

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Reviewer #1: Yes: Luke Nyakarahuka

Reviewer #2: No

Reviewer #3: No

Reviewer #4: No

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Submitted filename: Spatial distribution and determinants of abortion - Editors Comments.pdf

Click here for additional data file.

23 Feb 2020

Point by point response for editors and reviewers comments

Manuscript title: Spatial distribution and determinants of abortion among reproductive-age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey (EDHS) 2016 data: Spatial and Mixed-effect analysis

Manuscript ID: PONE-D-19-30532

Dear editor/reviewer.

Dear all,

We would like to thank you for these constructive, building and improvable comments on this manuscript that would improve the substance and content of the manuscript. We considered each comment and clarification questions of editors and reviewers on the manuscript thoroughly. Our point-by-point responses for each comment and questions are described in detail on the following pages. Further, the details of changes were shown by track changes in the supplementary document attached.

Response to editors

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming.

Authors’ response: Thank you, editor. We have prepared the manuscript according to PLOS ONE’s style. (see the revised manuscript)

2. Thank you for stating the following financial disclosure: "N/A"

Authors’ response: Thank you, editor. As we have stated in the documents, the study was done based on Ethiopian Demographic and Health Survey (EDHS) which is already available at measure DHS program. We request this program by sending the objectives of the study and we receive an authorization letter from the DHS program.

3. PLOS requires an ORCID iD for the corresponding author in Editorial Manager on papers submitted after December 6th, 2016. Please ensure that you have an ORCID iD and that it is validated in Editorial Manager. To do this, go to ‘Update my Information’ (in the upper left-hand corner of the main menu), and click on the Fetch/Validate link next to the ORCID field. This will take you to the ORCID site and allow you to create a new iD or authenticate a pre-existing iD in Editorial Manager. Please see the following video for instructions on linking an ORCID iD to your Editorial Manager account: https://www.youtube.com/watch?v=_xcclfuvtxQ

Authors’ response: We have created ORCID

4. We note that Figures 1, 3 and 5-7 in your submission contain map images which may be copyrighted.

Authors’ response: Thank you, editors, for your concern. The map is not copyrighted rather we have done using GIS software based on the shapefile of Ethiopia received from Ethiopian Central Statistical Agency (CSA) by explaining the purpose of the study and GPS data (longitude and latitude) from measure DHS program by explaining the objective of the study through online requesting and allow us to access the shapefile and GPS data. Now we cite the source of the shapefile since it is needed to explore the spatial distribution of abortion.

Response to reviewers’ comments

Reviewer # 1

1. Statistics in the result section could be summarised better, eg not over repeating 95% CI, only present the most important and interesting results eg you don’t have to put all the statistics for all the age groups,

Authors’ response: Thank you, reviewer, for your valuable comment. We accepted and corrected it. (See the revised manuscript)

2. Some repetitions in the conclusions

Authors’ response: Thank you, reviewer. We rewrite the conclusion section and remove the repetitions. (See the revised manuscript)

• Line 88, what do you mean by the wide gap in abortions

Authors’ response: Thank you, reviewer. We have stated in the Introduction section as there is wide gap in abortions across and within countries meanwhile we reviewed kinds of literature conducted on abortion the prevalence of abortion varied across countries and within countries and this gives an insight that abortion has been varied across countries and spatial study is needed to identify which areas are significant hotspot.

• Revise some sentences, Line 113 missing full stop, Line 121, do you mean sample size

Authors’ response: Thank you, reviewer. We have corrected it. (See the revised manuscript)

• Statistics, I think one appropriate method of model evaluations and evaluations could be chosen and be used

Authors’ response: Thank you, reviewer. We used AIC, BIC, and Deviance for model comparison but mainly we depend on Deviance since our models are nested models and we used ICC, AIC, and BIC as supportive.

• Line 245-249, two sentences all talking about high prevalence, which regions do you refer to them as high prevalence

Authors’ response: Thank you, reviewer, for your comments. It was an editorial error and the second one was areas with a low prevalence of abortion, we had modified in the revised document. (see the revised document)

• Figures are of poor quality, can be improved to publication quality.

Authors’ response: Thank you, reviewer, we had improved the figure quality using PACE in TIFF format (see the revised document)

Reviewer#2 #2:

1. First, a thorough grammatical editing is necessary, as the very first sentence has a spelling error (uretro)

Authors’ response: Thank you, reviewer, for the valuable comments. We accepted the comments and we corrected the grammatical errors extensively the entire manuscript. For Uretro it is corrected as the uterus (see the revised manuscript)

2. Secondly, the figures are not helping your analysis. Figure 1 is virtually illegible, Figure 2 needs to be a map at the regional level, with correctly capitalized region/state names. Furthermore, Figure 3 needs help, the points are far too small for the reader to understand anything about the spatial variation in the rate, Figure 4 can be eliminated as the Moran I statistic can be reported in the text. Adjust the number of decimal places on the maps, there are too many decimal values, you should report at most 2 decimal places.

Authors’ response: Thank you, reviewer, for your valuable comments. We were included Figure 1 to show the study area on the map and as you said it is not that much important and we removed in the revised manuscript. We have modified Figure 2 in ascending order based on the prevalence of abortion across regions by capitalizing on the name of the region. For Figure 3 the points were placed in decimal places and know we put in terms of percentage of abortion at enumeration areas by reducing the decimal places. We had removed Figure 4 as it is well stated in the form of text. (See the revised manuscript)

• Regarding your statistical model, it's more common to model the spatial variation using a CAR random effect in the binomial model, and visualize the random effect or the smoothed rate map, versus doing separate kriging or scan statistic methods.

Authors’ response: Thank you, reviewer, for the comments. We have done Kriging interpolation analysis for predicting the prevalence of abortion in unsampled areas based on observed data and SaTScan analysis to identify hotspot areas of abortion by running circular windows but we haven't done the Conditional Autoregressive (CAR) model and visualize the random effect because there are no covariates collected at Enumeration Area (EAs) level in EDHS data. Since the GPS data were collected at EA level but the covariates were collected at the individual level in EDHS data that is why we didn't do the CAR model to visualize the random effects with covariates.

• Why bother reporting the un-adjusted odd ratios? THis seems pointless to me, as you end up adjusting them anyway. Like wise, you do not need to report the weighted n in your table 1, just the %'s

Authors’ response: Thank you, reviewer. We accepted the comments and we removed the COR and the weighted n in table 1. (See the revised manuscript)

• Finally, you need to specify a hypothesis, there are no real research questions or testable hypotheses specified.

Authors’ response: Thank you, reviewer. The research questions in this study were

1. Whether the spatial distribution of abortion is random or not? Answered by Global spatial autocorrelation test (Moran’s Index)

2. Where are the significant hotspot areas of abortion in Ethiopia? Answered by SaTScan analysis

3. What are the factors that are significantly associated with abortion? Answered by GLMM (mixed-effect logistic regression analysis)

Reviewer #3

This is an interesting and well written paper documenting clustering of abortion in Ethiopia. The importance of the topic is well framed in the introduction, and the investigators use appropriate methods to draw conclusions.

Authors’ response: Thank you, reviewer.

My only suggestion is that the manuscript receive another read through to make minor edits to sentence structure for clarity.

Authors’ response: Thank you, reviewer. We extensively edit sentence structures and grammar with the help of language experts. (See the revised manuscript)

Reviewer #4

The authors present an interesting examination of the spatial distribution of abortion in Ethiopia using demographic and health survey data. The methods are appropriately used, with one question about whether the residuals were spatially autocorrelated in the model.

Authors’ response: Thank you, reviewer. We analyzed global spatial autocorrelation using Moran's Index and was significant. It revealed that the spatial distribution of abortion was non-random with Global Moran's I 0.06 (p<0.001) (significant spatial dependence). (See the revised manuscript)

1. Lines 25-27, line 63, line 65, line 67, line 69 and throughout. The authors should specify that “unsafe abortion” rather than “abortion” is a major cause of maternal mortality and a public health concern. Right now the two concepts are conflated.

Authors’ response: Thank you, reviewer. We have corrected as unsafe abortion in the document but in EDHS the data was collected as abortion it was not separately recorded as unsafe and safe abortion. (See the revised manuscript)

2. Line 33, line 36. Can the authors define abortion in this population? Is this the percentage of women interviewed who ever had an abortion? Or the percentage of previous pregnancies that ended in abortion?

Authors’ response: Thank you, reviewer. For this study, we define "abortion as the percentage of previous pregnancy that ended in abortion". (See the revised manuscript)

3. Throughout the authors talk about the rate of abortion and the prevalence of abortion. The authors need to define each, which I believe will have different meanings and interpretations. Are these prevalence of women ever having an abortion, prevalence of pregnancies ending in abortion, or what?

Authors’ response: Thank you, reviewer. You are right the rate of abortion and prevalence of abortion is different in meaning and interpretations. When we say the rate of abortion it is defined as the number of pregnancy ended in abortion per 1000 pregnancy whereas the prevalence of abortion is defined as the percentage of abortion per 100 pregnancy. For this study, we had reported the prevalence of abortion. (See the revised manuscript)

4. The authors should limit significant digits on figure 3. 0-5%, 5-15%, 15-28%, 28-50%.

Authors’ response: Thank you, reviewer. We have modified the maps as you recommend us. (See the revised manuscript)

5. The authors did not present the results from the global moran’s I of the residuals of their regression model. Was this non-significant, indicating that the model explained the spatial variance in the outcome? Or did the authors need to adjust their approach to account for spatially correlated data?

Authors’ response: Thank you, reviewer. We didn't do the spatially weighted regression since there is no covariate collected at the EA level. We did only the Global spatial autocorrelation, spatial interpolation, and SaTScan analysis.

6. For figure 5, I presume this is the LISA? Please indicate

Authors’ response: Thank you, reviewer. Figure 5 was Local indicators of spatial autocorrelation (LISA) using Getis Ord Gi statistics of hotspot analysis to identify significant hotspot areas and significant cold spot areas of abortion. As per the editors' comment, we had removed Figure 5 since we used SaTScan analysis to identify significant hotspot areas of abortion and this is very informative from a public health perspective.

7. The authors should limit significant digits on Figure 6 in a same manner as comment 4.

Authors’ Response: Thank you, reviewer. We have corrected by limiting significant digits. (See the revised Figure)

8. For figure seven I suggest using a single color for their hot spots identified (presuming these are all hotspots). They’re all significant.

Authors’ response: Thank you, reviewer. We have modified the figure as you suggest and we have clipped within the study area. (See the revised Figure)

9. I didn’t see a good subsection in the methods on the variables considered for the regression model. This needs to be better explained. In the table there was no urban/rural, which I would expect to be a significant factor.

Authors’ response: Thank you, reviewer. We have stated the variables considered for the regression model in the revised manuscript. The place of residence was one of the significant factors associated with abortion and it is already found in the regression table. (See the revised manuscript)

10. I think the authors would benefit from a copyeditor for the English.

Authors’ response: Thank you, reviewer. We had extensively edit the grammar and sentence structure with the help of Language experts. (See the revised manuscript)

Submitted filename: Point by Point response.docx

Click here for additional data file.

18 May 2020

PONE-D-19-30532R1

Spatial distribution and determinants of abortion among reproductive-age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey (EDHS) 2016 data: Spatial and Mixed-effect analysis

PLOS ONE

Dear Mr Tesema,

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.

Specifically, please address the issues raised in the attached pdf file. Additionally, the manuscript has numerous grammatical errors that render it not suitable for publication in its current form. Therefore, I strongly recommend that you get it reviewed and thoroughly edited by a native English speaker.

We would appreciate receiving your revised manuscript by Jul 02 2020 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.

To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). This letter should be uploaded as separate file and labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

We look forward to receiving your revised manuscript.

Kind regards,

Agricola Odoi, BVM, MSc, PhD, FAHA, FACE

Academic Editor

PLOS ONE

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

Reviewer #4: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #3: I have no further comments on this manuscript. All of my comments have been addressed in this revised manuscript.

Reviewer #4: (No Response)

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Luke Nyakarahuka

Reviewer #3: No

Reviewer #4: No

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4 Jun 2020

PLOS ONE

Point by point response for editors/reviewers comments

Manuscript title: Spatial distribution and determinants of abortion among reproductive-age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey (EDHS) 2016 data: Spatial and Mixed-effect analysis

Manuscript ID: PONE-D-19-30532R1

Dear editor/reviewer.

Dear all,

We would like to thank you for this constructive, building, and improvable comments on this manuscript that would improve the substance and content of the manuscript. Further, the details of changes we made is shown by track changes in the supplementary document attached. The manuscript language was checked by language professionals and we follow journal guideline. Response to Editors comments

1. Specifically, please address the issues raised in the attached pdf file. Additionally, the manuscript has numerous grammatical errors that render it not suitable for publication in its current form. Therefore, I strongly recommend that you get it reviewed and thoroughly edited by a native English speaker.

Authors’ response: Thank you Editor for the comments. We had extensively revised the manuscript. The grammar and editorial errors was extensively edited, and reviewed thoroughly with the help of language experts working at university of Gondar (See the revised manuscript).

Submitted filename: Point by point response.docx

Click here for additional data file.

16 Jun 2020

Spatial distribution and determinants of abortion among reproductive age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey 2016 data: Spatial and Mixed-effect analysis

PONE-D-19-30532R2

Dear Dr. Tesema,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Agricola Odoi, BVM, MSc, PhD, FAHA, FACE

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

19 Jun 2020

PONE-D-19-30532R2

Spatial distribution and determinants of abortion among reproductive age women in Ethiopia, Evidence from Ethiopian Demographic and Health Survey 2016 data: Spatial and Mixed-effect analysis

Dear Dr. Tesema:

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

Prof. Agricola Odoi

Academic Editor

PLOS ONE