Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia.

BACKGROUND: Short inter-pregnancy interval is an interval of <24 months between the dates of birth of the preceding child and the conception date of the current pregnancy. Despite its direct effects on the perinatal and maternal outcomes, there is a paucity of evidence on its prevalence and determinant factors, particularly in Ethiopia. Therefore, this study assessed the prevalence and associated factors of short inter-pregnancy interval among pregnant women in Debre Berhan town, Northern Ethiopia.
METHODS: A community based cross-sectional study was conducted among a randomly selected 496 pregnant women in Debre Berhan town from February 9 to March 9, 2020. The data were collected by using an interviewer-administered questionnaire and analyzed using STATA (14.2) statistical software. To identify the predictors of short inter-pregnancy interval, multivariable binary logistic regression was fitted and findings are presented using adjusted odds ratio (AOR) with 95% confidence interval (CI). RESULT: The overall prevalence of short inter-pregnancy interval (<24 months) among pregnant women was 205 (40.9%). Being over 30 years of age at first birth (AOR = 3.50; 95% CI: 2.12-6.01), non-use of modern contraceptive (AOR = 2.51; 95% CI: 1.23-3.71), duration of breastfeeding for less than 12 months (AOR = 2.62; 95% CI: 1.32-5.23), parity above four (AOR = 0.31; 95% CI: 0.05-0.81), and unintended pregnancy (AOR = 5.42; 95% CI: 3.34-9.22) were independently associated factors with short inter-pregnancy interval.
CONCLUSION: Despite the public health interventions being tried in the country, the prevalence of short inter-pregnancy interval in this study is high. Therefore, it implies that increasing contraceptive use and encouraging optimal breastfeeding might help in the efforts made to avert the problem.

Introduction

The inter-pregnancy interval is the time between the birth of the preceding child and the conception date of the current pregnancy. A short inter-pregnancy interval is when the interval between the delivery date of the preceding live birth and the conception date of the index birth is less than 24 months [1].

Historically, the World Health Organization (WHO) and other international authorities had recommended at least 2 to 3 years between successive pregnancies, and the United States Agency for International Development (USAID) had suggested an interval of 3 to 5 years [1]. Given the inconsistency, various countries and regional programs requested the WHO to further review the research and provide recommendations. As a result, the report of the 2005 WHO Technical Consultation and Scientific Review of Birth Spacing recommended waiting at least 2 years after a live birth and 6 months after miscarriage or induced termination before conception of another pregnancy [1].

A short inter-pregnancy interval (IPI) is associated with adverse maternal and infant health outcomes. It is known to hurt perinatal, neonatal, and child health outcomes, including preterm birth, low birth weight, perinatal death, still birth, intellectual disability, and developmental delay. Besides, it has also adverse maternal health outcomes such as nutritional depletion, anemia, cervical insufficiency, antepartum hemorrhage, premature rupture of membrane, and eclampsia [2-6].

In low-income countries, the prevalence of short inter-pregnancy interval ranges from 19.4% to 65.9% [4,7]. Even though there are studies in developed and some low-income countries, there is a paucity of evidence on the prevalence and predictors of inter-pregnancy interval in Ethiopia regardless of the country’s culture encouraging women to have many children. On top of this, there are limitations of the currently available literature.

Most of the researches used birth interval, a proxy measure of time between two consecutive births, which could under or overestimate the time interval between the birth date of the preceding child and the conception date of the pregnancy. However, this study used the inter-pregnancy interval which measures correctly the time elapsed between the date of birth of the preceding child and the conception date of the current pregnancy. Therefore, the result of this study could present a more accurate picture of the problem and aid in the efforts being tried to reduce the short inter-pregnancy interval. The aim of this study was to assess the prevalence and associated factors of short inter-pregnancy interval among pregnant women in Debre Berhan town, Northern Ethiopia.

Methods and materials

Study setting, design and period

This community based cross-sectional study was conducted in Debre Berhan town, North Shewa zone, Northern Ethiopia from February 9 to March 9, 2020. We selected Debre Berhan town because it was the largest town in North Shewa zone where we can find the larger proportion of women compared to other towns of the zone and considering the available budget to conduct the study. The town is located 130 km from Addis Ababa, and it has nine kebeles. Kebele is the smallest administrative region in Ethiopia, approximately comprising 1,000 households. The total number of populations in the town is 57,787. The characteristics of the population in all the 9 kebeles is more or less similar. There are 795 pregnant women in these kebeles who are registered by health extension workers. In the town, there are 29 health institutions: two hospitals (one private and one referral governmental hospital), 3 health centers, 17 drug stores, and 7 private specialty clinics. In the health centers and hospitals of Ethiopia, midwives are the primary point of care for all pregnancies.

Populations

Pregnant women who gave birth at least once (uniparous) and live in Debre Berhan town were the source population of this study. Women who had a miscarriage/abortion immediately before the current pregnancy were excluded from the study because they are more likely to get pregnant earlier as a result of the pregnancy loss, and they are recommended to have an interval of only six months.

Sample size determination and sampling procedure

The sample size was determined using Epi info version 7 considering 28.5% prevalence of short inter-pregnancy interval from the study done in Bahir Dar Felegehiwot Hospital [8]. The final sample size was determined as 517 after considering a design effect of 1.5 and a non-response rate of 10%. Simple random sampling technique was used to select the kebeles and the participants. Among the nine kebeles, five kebeles were randomly selected. Then the sample size was proportionally allocated to those five kebeles. Family folder from the hands of Health Extension Workers (HEWs) of each kebele was used as a sampling frame to obtain a list of pregnant women in each kebele, and computer-generated random numbers were identified by the principal investigator and printed out to be given to the data collectors. Then, the data collectors visited the household of the study participants to conduct the interview.

Data collection procedure and quality management

A structured interviewer administered questionnaire was prepared and implemented after reviewing relevant literature. The questionnaire was prepared in English then translated into the local language (Amharic) and finally translated back to English to check its consistency. It consists of socio-demographic, reproductive and health service related factors. It was checked and pre-tested in 5% of the study population outside the selected kebeles. After training was given for two days, the data were collected by five diploma midwives through a home-to-home visit. Revisits of two to three times were made for women who were not available at the time of the survey. The collected data were checked for completeness and consistency on each day of data collection. Supervision and monitoring were made every day by the assigned supervisors and the principal investigator.

Measurement

Inter-pregnancy interval was defined as the time in completed months from the reported date of live birth of the previous child to the self-reported last normal menstrual period (LNMP). Most participants knew the date of birth of the previous child and last normal menstrual period of the current pregnancy. However, in case of the participants who didn’t know the specific date of conception and/or the birth date of the previous child, the mid-date of the month was taken as the birth date of the previous child or the date of the conception for the current pregnancy. Therefore, the inter-pregnancy interval was calculated by subtracting the date of birth of the last child (previous child) from the date of conception of the current pregnancy (IPI = date of conception (LMP)—date of birth of the previous child). So, short inter-pregnancy interval was defined as an interval less than 24 months.

Data processing and analysis

The data were entered, cleaned and processed by Epi-data version 3.1 software and exported to STATA version 14.2 for analysis. (The analyzed data are provided with S1 File). Descriptive statistics such as frequencies, proportions and summary statistics were used to describe the study population with relevant variables. Association between the outcome and explanatory variables was assessed by using a binary logistic regression model. Variables with a p-value of ≤ 0.2 in bivariable analysis were entered together into the model to conduct a multivariable analysis so as to control their effects of confounding. Statistical significance was considered at a level of significance of 5%, and adjusted odds ratio along with a 95% confidence interval was used to present the estimates of the strength of the associations. Hosmer-Lemeshow and variance inflation factor (VIF) was used to test the model fitness and multicollinearity respectively.

Ethical consideration

Ethical clearance was obtained from the Ethical Review Committee of the Debre Berhan University. Then a permission letter from the Debre Berhan town health office and Debre Berhan town administration office was obtained. Moreover, the informed written consent was obtained from each respondent. Personal identifier such as name was not mentioned in the questionnaire.

Results

Socio-demographic characteristics of the study participants

A total of 496 pregnant women was included in the study yielding a response rate of 96%. The age of the participants ranged from 20 to 42 with the mean age (±SD) of 29.5 (±4.7) years. Of the study participants, around half (52.22%) were between the age of 25 to 29 years. One hundred seventy-three (34.88%) of the participants had attended college and above in their educational status, and 413 (83.26%) were orthodox Christians by religion (Table 1).

Table 1

Socio-demographic characteristics of the study participants, Debre Berhan town, Amahra region, Ethiopia, 2020.

Characteristics	Frequency (n = 496)	Percent (%)
Current maternal age
20–24 years	43	8.66
25–29 years	259	52.22
30–34 years	110	22.17
35–39 years	61	12.29
≥ 40years	23	4.63
Maternal age at first birth
≤ 30 years	415	83.67
>30 years	81	16.33
Religion
Orthodox	413	83.26
Muslim	39	7.86
Protestant	44	8.87
Current maternal occupational status
Self employed	81	16.33
Private employee	76	15.32
Government employee	147	29.64
Housewife	183	36.89
Student	9	1.81
Husband’s occupation
Self employed	155	31.25
Private employee	86	17.34
Government employee	236	47.58
Other	19	3.83
Household monthly income
< 1000 ETB	27	5.44
1000–2999	46	9.27
3000–4999	95	19.15
> 5000	328	66.13

Reproductive and health service related factors of the study participants

One hundred ninety-six (39.52%) of the participants did not use modern contraceptive before the current pregnancy, and 108 (21.77%) participants had an unintended pregnancy. Forty-eight (9.67%) of the study participants had no antenatal care (ANC) follow up by skilled attendants during the pregnancy of the index child. Similarly, forty-nine (9.87%) of the participants provided breastfeeding of their index child for only less than 12 months. Seventy-one (14.31%) participants had children of four and above, excluding the current pregnancy (Table 2).

Table 2

Reproductive and health service related factors of pregnant women in Debre Berhan town, Amahra region, Ethiopia, 2020.

Characteristics	Frequency (n = 496)	Percent (%)
Use of contraceptive before the current pregnancy
Yes	300	60.48
No	196	39.52
ANC visit for the index child
Yes	448	90.32
No	48	9.67
Exclusive breastfeeding for the index child
< 2 months	87	17.54
2–3 months	74	14.92
4–5 months	69	13.91
6–7 months	253	51.00
Above 7 months	13	2.62
Total duration of breastfeeding for the index child
≤12 months	49	9.87
13–23 months	136	27.42
24 and above months	311	62.70
Parity
<4	425	85.68
≥4	71	14.31
Pregnancy intention
Intended	388	78.22
Unintended	108	21.77
Survival status of the index child
Alive	480	96.77
Dead	16	3.22
Sex of the index child
Female	262	52.82
Male	234	47.18
Menstrual cycle pattern
Regular	283	57.05
Irregular	213	42.94
History of infertility
Yes	26	5.24
No	470	94.75
Mode of delivery of the index child
Vaginal	431	86.89
Cesarean section	65	13.10

Prevalence of short inter-pregnancy interval

The prevalence of short inter-pregnancy interval (< 24 months) of this study was 205 (40.9%) with 95% CI: 36.6 to 45.4%. The median (IQR) inter-pregnancy interval of the study participants was 29 (18, 48) months. Of those who had a short inter-pregnancy interval, 24 (5%) had very short inter-pregnancy interval (<12 months). Besides, 210 (42%) and 86 (17.2%) of the participants had an inter-pregnancy interval of 24 to 59 months and more than 60 months, respectively.

Factors associated with short inter-pregnancy interval

Bivariable and multivariable logistic regression analyses were carried out to determine the association between the explanatory variables and short inter-pregnancy interval. Hence, based on the p-value (< 0.2) of the bivariable analysis, current maternal age, age at first birth, parity, unintended pregnancy, non-use of modern contraceptive before the current pregnancy, duration of breastfeeding, and survival status of the index child were selected as candidate variables to be included in the final model. However, the result of multivariable analysis confirmed that age at first birth, parity, unintended pregnancy, non-use of modern contraceptive before the current pregnancy, and duration of breastfeeding were independently associated with short inter-pregnancy interval. Multicollinearity was checked using a variance inflation factor and yielded a result of <10 for all variables in the final model (Table 3).

Table 3

Bivariable and multivariable binary logistic regression analyses results of factors associated with short inter pregnancy interval among pregnant women in Debre Berhan town, Amahra region, Ethiopia, 2020.

Variable	Short inter-pregnancy interval (in months)		COR (CI: 95%)	AOR (CI: 95%)	p-value
	Yes (n, %)	No (n, %)
Current age of respondent
20–24 years	24(55.81)	19 (44.19)	1.94(1.01–3.72)*	1.84(0.836–4.04)	0.1
25–29 years	104(40.15)	155(59.85)	1	1	-
30–34 years	47(42.73)	63(57.27)	1.15 (0.73–1.80)	1.41(0.84–2.36)	0.2
35–39 years	21 (34.43)	40(65.57)	0.81 (0.45–1.44)	1.06(0.53–2.11)	0.8
>= 40 years	9(39.13)	14(60.87)	0.98(0.41–2.36)	1.49(0.49–4.47)	0.5
Age at first birth
<= 30 years	151 (36.39)	264(63.61)	1	1	-
>30 years	54 (66.66)	27 (33.33)	3.61 (2.15–5.89) *	3.50(2.12–6.01)	<0.001*
Use of contraceptive before the current pregnancy
Yes	115(36.98)	196(63.02)	1	1	-
No	90(48.65)	95(51.35)	2.05(1.42–2.96) *	2.51(1.23–3.71)	0.007*
Duration of breastfeeding for the index child
≤12 months	29(59.18)	20(40.82)	2.46 (1.33–4.55) *	2.62(1.32–5.23)	0.006*
13–23 months	59(43.38)	77(56.62)	1.30 (0.86–1.96)	1.21(0.74–1.95)	0.4
24 and above months	117(37.62)	194(62.38)	1	1	-
Parity
<4	164(38.58)	261(61.41)	1	1	-
≥4	41(57.74)	30(42.25)	0.17(0.08–0.35) *	0.31(0.05–0.81)	<0.001*
Pregnancy intention
Intended	133 (34.27)	255(65.72)	1	1	-
Unintended	72 (66.66)	36(33.33)	3.91(2.48–6.14) *	5.42(3.34–9.23)	<0.001*
Survival status of the index child
Alive	193(40.21)	287(59.79)	1	1	-
Dead	12	4	4.54(1.44–14.27) *	2.97(0.80–11.03)	0.1

* = statically significant at p-value of ≤ 0.05, COR = crude odds ratio, AOR = adjusted odds ratio.

Discussion

A community based cross-sectional study was conducted to assess the prevalence and associated factors of the short inter-pregnancy interval among pregnant women of the Debre Berhan town. Consequently, the overall prevalence of short inter-pregnancy interval (< 24 months) among pregnant women was 205 (40.9%). The factors independently associated with short inter-pregnancy interval were age at first birth, parity, unintended pregnancy, non-use of modern contraceptive before the current pregnancy, and duration of breastfeeding.

The prevalence in this study is higher than the studies in Bahidar, Felegehiwot Hospital [8] and the United States (US) [9] where about 28.5% and 35% of women had short inter-pregnancy interval respectively. This difference might be attributed to the cut off point for short inter-pregnancy interval. In this study, the cut off point for short inter-pregnancy interval was < 24 months. In comparison, the study conducted in the US and rural health center Manga Mandi, District Lahore defined short inter-pregnancy interval to be less than 18 months [9,10]. On the other hand, this finding is lower compared to the study conducted in Nigeria [7] and Selangor [11] where the prevalence of short inter-pregnancy interval is 65.9% and 48% respectively. This difference might be attributed to the sample population and sociocultural practice.

In this study, the odds of experiencing short inter-pregnancy interval was 3.5 times higher among women who started child bearing above the age of 30 years compared to those who start at 30 years of age and lower. This finding is consistent with the study done in Bahirdar (Felegehiwot hospital) [8], and the US [9,12]. This might be due to the intention to use the remaining fertility age efficiently before the woman reaches the stage of menopause. In line with the evidence from two studies done in Nigeria [7,13], the finding of this study revealed that women who did not use modern contraceptive before the current pregnancy had 2.5 times higher odds of experiencing short inter-pregnancy interval as compared to those who used it. This can be explained by the potential of modern contraceptive to prevent and extend pregnancy.

This study also found out unintended pregnancy to be associated with short inter-pregnancy interval. The odds of experiencing short inter-pregnancy interval was 5.4 times higher among women with unintended current pregnancy compared to their counterparts. This finding is congruent with the study conducted in the US [9] and Selangor [11]. This might be due to a woman who plan to be pregnant may follow the recommendation for child spacing and therefore end up with optimal inter-pregnancy interval. “Since non-utilization and failure of contraceptive are among the major contributors of the unintended pregnancy, this might have contributed to the shortened inter-pregnancy interval” [14]. This study revealed that the odds of short inter-pregnancy interval was 2.6 times higher among women who breastfed their last child for less than 12 months compared to those who breastfed for 24 and above months. This finding is in line with the evidence from the study done in Nigeria [7]. It might be due to the fact that the duration of breastfeeding, including exclusive breastfeeding improves infant survival and lengthens the interval between pregnancies due to lactational amenorrhea (negative hormonal feedback). During breastfeeding, the receptors in the breast nipple will be stimulated, and this initiates a signal to the hypothalamus: a nerve center in the brain, which in turn signals the pituitary gland, thereby inhibits ovulation by reducing the release of gonadotrophic hormone needed for ovulation which results in post-partum amenorrhea [15].

The study also showed that parity was negatively associated with short inter-pregnancy interval. Women who had four and above children had 70% lower odds of experiencing short inter pregnancy interval compared to the counter groups. This finding is in line with the study done in Nigeria [13] and rural Bangladesh [16], but in contrast with the study done in Selangor [11]. These women may have achieved their desired family size and may feel less pressure or may be in a less hurry to get pregnant again.

Limitation

The inter-pregnancy interval and breast-feeding duration were calculated based on women recall, which might result in recall bias. Being the data obtained through self-report of the women, the accuracy might not be at a level obtained objectively, even though respondents were critically informed about giving accurate information through assuring the confidentiality of their responses. The exclusion of women who experienced miscarriage/abortion immediately before the current pregnancy might have underestimated the prevalence of the short inter pregnancy interval.

Conclusion

The World Health Organization (WHO) and the government of Ethiopia recommended that a woman should wait 24 months before attempting the next pregnancy after a live birth. Despite this recommendation, this study found out a higher proportion of women (40.9%) getting pregnant before the recommended period of time. Age at the first birth, parity, non-use of modern contraceptive, duration of breastfeeding, and unintended pregnancy were independently associated with short inter-pregnancy interval in the study. Therefore, it implies that increasing contraceptive use and encouraging optimal breastfeeding might help in the efforts made to avert the problem. Besides, further studies in the rural setup with higher sample size are needed to ascertain the prevalence and determinants of short inter-pregnancy interval.

Dataset of the study.

(XLSX)

Click here for additional data file.

Questionnaire of the study.

(DOCX)

Click here for additional data file.

13 Apr 2021

PONE-D-21-08455

Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia

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Reviewer #1: PLOS One Review: Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan Town, Ethiopia

Dear PLOS One Editorial Board and authors of this manuscript,

I would first like to acknowledge and commend the work preformed by this group. The questions they asked are of particular importance, not only in Debre Berhan Town but globally as well, and paramount to the understanding of maternal health and development of children. Without first an understanding of the frequency of and factors that lead to a short interpregnancy interval it is impossible to then work on making changes, improve health and awareness for the society and future research projects. Additionally, I find it personally impressive that they were able to enroll and receive responses from nearly 500 people in a short, one month time frame – an indication in my mind that they are committed and focused on applying the data and making true change in their community not merely publishing another paper. Further, a 500 individual sample size is of course quite robust.

The goal of this paper was, as is clearly stated in their title, to determine how common a short interpregnancy interval is and what variables are correlated and associated to it specifically in Debre Berhan Town, Ethiopia. They preformed a cross sectional study using 5 midwives to sample pregnant mothers in 5 of 14 randomly selected kebeles (which my understanding act as areas/neighborhoods within Debre Berhan Town) and then pregnant mothers were sampled proportionately among those 5 kebeles at random. These mothers were then given a questionnaire administered by the midwives, each of whom sampled one kebele. For the purpose of pregnancy, abortions and miscarriages were not counted which I will discuss further in a moment. This study found that 40.9% of sampled women were pregnant again within this World Health Organization suggested period. Per their clearly written conclusion, “Age at the first birth, parity, non-use of modern contraceptive, duration of breast feeding, and unintended pregnancy were independently associated with short inter-pregnancy interval in the study. Therefore, it implies that increasing contraceptive use and encouraging optimal breast feeding might help in the efforts made to avert the problem.”

This manuscript is written clearly and such that non-specialists in the field can certainly understand, but some clarification with regard to customs and structure within Debre Berhan Town, Ethiopia would be beneficial as is discussed further bellow.

Before moving forward and addressing the areas left for improvement and questions that should be asked or considered in this paper, I would first like to make two points which may explain some of the points I am about to make:

1) I acknowledge that the patient data was collected from February 9th to March 9th of 2020, ending just a few days prior to the WHO declaration that there was a global pandemic caused by sars-cov-2 (COVID-19). It is conceivable that a larger study was originally planned.

2) I am not entirely familiar with what life is like in Debre Berhan Town, Ethiopia – as I imagine is the case for most people who will read this publication. As such, I may be missing some information that is needed to fully understand the authors position or the nature of pregnancy care and labor. While I was able to find some of this information online, such as population size and what definition of a Kebele, more of this information should be stated clearly in the manuscript.

Here are my points for improvement and/or clarification:

1) Why only Debre Berhan Town, Ethiopia?

a. I can make the assumption that this is because this is where the authors work and where their funding is from, however, it should be stated clearly.

b. Is this town particularly at risk for having a low interpregnancy duration?

2) With regard to Kebeles and addressing sample representation of Debre Berhan Town, Ethiopia:

a. Define a Kebele better early in the paper

b. Determine whether or not the 5 kebeles – while randomly selected – are indicative of the general population.

i. Ie. Were they the wealthiest or poorest kebeles? Do all kebeles have similar structural make up? Do all kebeles have access to the same healthcare? There are some socioeconomic techniques that can be used to preform these statistics if not readily available.

3) Describe access to healthcare in Debre Berhan Town and how women normally give birth, particularly in relation to the fact that in this study only midwives were used to gather all of the data (important for generalization ability and potential sources of bias):

a. What percentage of women give birth with a midwife as opposed to physician, family alone, c-section etc?

b. Do midwives take care of all pregnancies?

i. Ie if a mother is particularly ill or there is a complication with the pregnancy, does a midwife provide the care? If not, then there is selection bias against this group.

c. Paper should either be rewritten to reflect it is looking at this subset of pregnancies/births if this is the case or address other forms of birth as well.

4) Perhaps some co-variables could be looked at together, not simply alone.

5) “Family Planning” and interventions are mentioned in introduction. This raises the following points for this manuscript:

a. It is mentioned that the interpregnancy period is short, despite these interventions. Was there data from before that the new data presented in this paper can be presented against?

b. Family planning does not seem to be discussed further in the manuscript but should be considered as a variable, unless everyone has this training – in which case that needs to be stated.

6) Abortions and miscarriages were not counted as pregnancies, but equally was also not considered as a variable which seems short sighted as it can be incredibly impactful on a mother and family.

a. Excluding these cases can lead to under reporting the data and leading to the data, and thus study, being less generalizable.

b. Why were they excluded?

i. Would the following situation be considered as a pregnancy interval: Birth 1, miscarriage, birth 2? Would the mother be excluded from the study? Or would the miscarriage merely not be considered?

c. What is the abortion rate and miscarriage rate in Debre Berhan Town, Ethiopia?

d. I do acknowledge that infant mortality rates and maternal infertility history are considered and may reflect some of these concerns. If so, please discuss and address this fact more specifically.

To reiterate it is my belief that the authors conducted important research with an impressive work ethic and sample size, while focusing on what I ascertain to be important and actionable variables for their situation, which can likely be generalized to other areas of a similar nature.

There are no ethical concerns or statistical interpretation concerns.

It is my formal recommendation that the Editors accept this paper after minor revisions are completed to clarify the aforementioned points and I encourage the authors to continue this line of inquiry for the betterment of the community they are serving but also the global research community that is also focusing on the effects and associated factors of short interpregnancy time. There is potential for further, more in-depth research into the well-being of the mother and children from this study, as the impact of a short interpregnancy period is not studied beyond the introduction. Additionally, a sociological and psychological approach to understanding the influences behind a short interpregnancy interval would certainly be interesting and add another level of depth to this paper. However, this would change the nature of this manuscript significantly and is not needed to finalize a publishable product.

I wish the authors the best in their efforts to help their community and contribute meaningfully to the international research community. It has been a privilege to review their work, and I am appreciative of this opportunity.

Kindly,

The Reviewer

Reviewer #2: ABSTRACT: Under background, the definition of interpregnancy interval (1st sentence) should be recasted for better understanding. Grammatical errors that need to be corrected.

INTRODUCTION: Lines 5-7,page 3,paragraph 2 should be referenced. Page 3, paragraph 3,lines 14-18 should be recasted.

METHODS: Why was Debre Berham chosen as the study location? The authors should explain what kebeles are for international readers. There should be a more detailed explanation as to how the pregnant women were selected, where this was done, by whom and when? When were the questionnaires administered and where was this done?

DISCUSSION: Lines 8,page 11,US should be written in full 1st. Also RHC (lines 11,page 8.) In page 12,lines 8 and line 10 when referencing statements, the authors mix cities and countries in different references.eg Port-Harcourt (reference 13) is a town in Nigeria but reference 7 is Nigeria. Also US (reference 9) then Michigan reference 12. The referencing of statements should be uniform for better understanding. Page 12,line 13-14 should be recasted. The literature review should be more robust.

CONCLUSION: The statement in the last line in the conclusion in page 13, including the non-use of contraceptive as part of the recommendations reduce the incidence of short interpregnancy intervals seems to be at variance with the information in the last paragraph of the discussion before the limitations.

REFERENCES>NO 6- BMJ should be written in full

**********

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Reviewer #1: No

Reviewer #2: No

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7 May 2021

Dear reviewers and editor,

Thanks for your review and important issues you raised in the paper. Hereunder, kindly get the responses to the points raised.

Response to editor

1. I have uploaded the questionnaire (both English version and Amharic version) as Supporting Information.

2. A copy of supporting information file 1 (the dataset of the study) was also uploaded in the system.

Responses to Reviewer #1

1. We selected Debre Berhan town because it was the largest town in North Shewa zone where we can find the larger proportion of women compared to other towns of the zone and considering the available budget to conduct the study. (stated in the manuscript)

b) Generally, the culture of Amhara region where Debre Berhan town is located, encourages giving birth of too many children

2. Kebele was defined as “Kebele is the smallest administrative region in Ethiopia approximately comprising 1,000 households.” in the manuscript. The characteristics of the population in all the 9 kebeles is more or less similar. (stated in the manuscript)

3. Relevant information in the study area including access to health care are included in the revised manuscript such as “In the town, there are 29 health institutions: two hospitals (one private and one referral governmental hospital), 3 health centers, 17 drug stores, and 7 private specialty clinics.” And in Ethiopia, the midwives give basic care to all pregnancies and refer those women with serious complications needing urgent referral to hospitals. To eliminate selection bias, the participants were selected randomly from the family folder, and the printed hardcopies were given to the data collectors to access the women and make interview. Besides, being a community-based study, the sampling will not depend on the level of care that the midwives will give.

4. We tried to check for possible interaction of variables; however, we haven’t found significant and/or plausible result.

5. The issue of family planning and interventions were also addressed in the revised manuscript. Actually, it was mentioned not in the background section but in the abstract subsection conclusion and now it’s fixed.

6. Women who had miscarriage/abortion immediately before the current pregnancy were excluded from the study because they are more likely to get pregnant earlier as a result of the pregnancy loss, and they are recommended to have an interval of only six months. Because of the difference in the recommended interval between the pregnancies for those who experienced abortion immediately before the current pregnancy and who didn’t, we excluded them not to overestimate the short interpregnancy interval in a biased manner.

However, those women who were recorded as pregnant in the family folder but had abortion at the study period were not excluded. Despite these, the possibility of bias associated with the exclusion was discussed in the limitation of the manuscript.

Besides, we could not find a true figure of abortion rate and miscarriage rate in Debre Berhan Town as per our search.

Responses to Reviewer #2

ABSTRACT: Under background, the definition of interpregnancy interval (1st sentence) was recast and corrected in the revised manuscript.

INTRODUCTION: Lines 5-7,page 3,paragraph 2 was referenced. Page 3, paragraph 3, lines 14-18 was recast.

METHODS: Concerning “Why was Debre Berham chosen as the study location?” And definition of kebeles, kindly see the responses to reviewer 1 under #1 and #2, respectively.

A more detailed explanation as to how the pregnant women were selected was added in the revised manuscript.

DISCUSSION: Lines 8,page 11,US was written in full 1st. Also RHC (lines 11,page 8.) In page 12, line 8 and line 10 the referencing issue, the authors mix cities and countries in different references was fixed, and the cities were replaced by the respective countries to make it consistent and for better understanding.

Page 12, line 13-14 was recast.

CONCLUSION: “The statement in the last line in the conclusion in page 13, including the non-use of contraceptive as part of the recommendations reduce the incidence of short interpregnancy intervals seems to be at variance with the information in the last paragraph of the discussion before the limitations.” Was addressed in the revised manuscript.

REFERENCES>NO 6- BMJ should be written in full. It is the journal’s actual name, and it’s how they suggest to cite their journal

With kind regards,

The authors

Submitted filename: Rebuttal Letter 2 revised.docx

Click here for additional data file.

22 Jun 2021

PONE-D-21-08455R1

Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia

PLOS ONE

Dear Dr. Kotiso,

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.

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

This manuscript has been improved by the various revisions made. Both reviewers have suggested further (minor) revisions. I think that they would improve the manuscript once again, so please attend to each one of the suggestions to make the manuscript as good as it can possibly be. I will not add to the various suggested revisions, which should not be too onerous for the authors to deal with. I look forward to seeing the next version of the manuscript.

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

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Academic Editor

PLOS ONE

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Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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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: (No Response)

Reviewer #2: (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 #2: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: I Don't Know

**********

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 #2: 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 #2: No

**********

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: Dear Authors,

Thank you for addressing my comments thoroughly and making appropriate adjustments to the manuscript. Please see the last few areas of improvement after which, I believe this manuscript will be ready for publication.

Introduction:

In the sentence "Therefore, the result of this study could present a true picture of the problem and aid in the efforts being tried to reduce the short inter-pregnancy interval." I suggest replacing the word "true" with "more accurate"

Study setting/Background:

Mention the culture often leads to women having too many children

Mention midwives are primary point of care for all pregnancies

Response 3: sampling may not change but it is important for the generalizability and validity of the paper.

Response 5 - thank you, I apologize for missing it.

Response 6 -thank you for the thorough further explanation.

I look forward to reading the final draft. Again, I note the importance of the research the authors have undertaken.

Kindly,

The Reviewer

Reviewer #2: GENERAL: Few grammatical errors and wrong tenses

METHODS: Under population (page 4), the 1st sentence should better read- Pregnant women who give birth a least once----.

DICUSSION: In page 13,line 3-4; This study is in line with a study done in Nigeria (13, 16) and Bangladesh (16). Reference number 16 is quoted for a study done in both Nigeria and Bangladesh.

REFERENCES: Number 6-bmj should be in capital letters. The paging in reference number 7 is not complete

**********

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: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

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.

16 Jul 2021

Dear reviewers and editor,

Thank you for your review and important issues you raised in the manuscript entitled “Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia.”

We have read the reviewer's comments carefully and hope that the revised version now submitted will be regarded as having enhanced the previous version. The authors very welcome the reviewer's comments and suggestions. These contributions have appreciably improved the final paper quality. Hereunder, kindly get the responses to the points raised under each point.

Response to reviewers

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: (No Response)

Reviewer #2: (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 #2: Yes

________________________________________

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

Reviewer #1: Yes

Reviewer #2: I Don't Know

________________________________________

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 #2: 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 #2: No

________________________________________

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:

Introduction:

In the sentence "Therefore, the result of this study could present a true picture of the problem and aid in the efforts being tried to reduce the short inter-pregnancy interval." I suggest replacing the word "true" with "more accurate"

Comment: true was replaced by more accurate based on the reviewer’s comment

Study setting/Background:

Mention the culture often leads to women having too many children

Mention midwives are primary point of care for all pregnancies

Comment: amendments were made based on the reviewer’s comment.

Response 3: sampling may not change but it is important for the generalizability and validity of the paper.

Comment: thank you for the important notice.

Response 5 - thank you, I apologize for missing it.

Response 6 -thank you for the thorough further explanation.

Reviewer #2:

GENERAL: Few grammatical errors and wrong tenses

Comment: Some grammatical errors were fixed based on the reviewer’s comment.

METHODS: Under population (page 4), the 1st sentence should better read- Pregnant women who give birth a least once----.

Comment: Corrections were made based on the reviewer’s comment.

DICUSSION: In page 13,line 3-4; This study is in line with a study done in Nigeria (13, 16) and Bangladesh (16). Reference number 16 is quoted for a study done in both Nigeria and Bangladesh.

Comment: reference number 16 is removed from a study done in Nigeria.

REFERENCES: Number 6-bmj should be in capital letters. The paging in reference number 7 is not complete

Comment: bmj was capitalized, and the paging in reference 7 was made complete.

Thank you for your consideration. We look forward to hearing from you.

Sincerely,

The authors

21 Jul 2021

Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia

PONE-D-21-08455R2

Dear Dr. Kotiso,

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.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Clive J Petry, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

23 Jul 2021

PONE-D-21-08455R2

Prevalence of short interpregnancy interval and its associated factors among pregnant women in Debre Berhan town, Ethiopia

Dear Dr. Kotiso:

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.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

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Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

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on behalf of

Dr. Clive J Petry

Academic Editor

PLOS ONE