Interpregnancy interval and perinatal outcomes across Latin America from 1990 to 2009: a large multi-country study

A Framework for Neonatal Prematurity Information System Development Based on a Systematic Review on Current Registries: An Original Research

Background

Registries are regarded as a just valuable fount of data on determining neonates suffering prematurity or low birth weight (LBW), ameliorating provided care, and developing studies.

Objective

This study aimed to probe the studies, including premature infants' registries, adapt the needed minimum data set, and provide an offered framework for premature infants' registries.

Material and Methods

For this descriptive study, electronic databases including PubMed, Scopus, Web of Science, ProQuest, and Embase/Medline were searched. In addition, a review of gray literature was undertaken to identify relevant studies in English on current registries and databases. Screening of titles, abstracts, and full texts was conducted independently based on PRISMA guidelines. The basic registry information, scope, registry type, data source, the purpose of the registry, and important variables were extracted and analyzed.

Results

Fifty-six papers were qualified and contained in the process that presented 51 systems and databases linked in prematurity at the popular and government levels in 34 countries from 1963 to 2017. As a central model of the information management system and knowledge management, a prematurity registry framework was offered based on data, information, and knowledge structure.

Conclusion

To the best of our knowledge, this is a comprehensive study that has systematically reviewed prematurity-related registries. Since there are international standards to develop new registries, the proposed framework in this article can be beneficial too. This framework is essential not only to facilitate the prematurity registry design but also to help the collection of high-value clinical data necessary for the acquisition of better clinical knowledge.

Association between interpregnancy interval and gestational diabetes mellitus: A cohort study of the National Vital Statistics System 2020

OBJECTIVE

To assess the association between interpregnancy interval (IPI) and gestational diabetes mellitus (GDM).

METHODS

Data of this retrospective cohort study were obtained from the National Vital Statistics System (NVSS) 2020. The participants were divided into different groups according to different IPI (<6, 6-11, 12-17, 18-23, 24-59 (reference), 60-119, ≥120 months). Multivariate logistic models were constructed to evaluate the association between IPI and GDM. Subgroup analysis was further performed.

RESULTS

A total of 1 515 263 women were included, with 123 951 (8.18%) having GDM. Compared with the 24-59 months group, the <6 months (odds ratio [OR] 0.64, 95% confidence interval [CI] 0.46-0.90, P = 0.009), 12-17 months (OR 0.96, 95% CI 0.94-0.98, P < 0.001), and 18-23 months (OR 0.94, 95% CI 0.93-0.96, P < 0.001) groups had a significantly lower risk of GDM, while the 60-119 months (OR 1.13, 95% CI 1.11-1.15, P < 0.001) and ≥120 months (OR 1.18, 95% CI 1.15-1.21, P < 0.001) groups had a significantly higher risk of GDM. No significant difference was observed in the risk of GDM between the 6-11 and 24-59 months groups (P = 0.542). The PI-GDM association varied across different groups of age, pre-pregnancy body mass index, pre-pregnancy smoking status, history of cesarean section, history of preterm birth, prior terminations, and parity.

CONCLUSION

An IPI of 18-23 months may be a better interval than 24-59 months in managing the risk of GDM.

Interactions between long interpregnancy interval and advanced maternal age on neonatal outcomes

BACKGROUND

After the implementation of the universal two-child policy in China, it was more frequent to have long interpregnancy intervals (IPIs) and advanced maternal age. However, the interactions between long IPIs and advanced maternal age on neonatal outcomes are unknown.

METHODS

The study subjects of this historical cohort study were multiparas with singleton live births between October 1st, 2015, and October 31st, 2020. IPI was defined as the interval between delivery and conception of the subsequent pregnancy. Logistic regression models were used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) of the risks of preterm birth (PTB), low birth weight (LBW), small for gestation age, and 1-min Apgar score ≤ 7 in different IPI groups. Relative excess risk due to interaction (RERI) was used to evaluate the additive interaction between long IPIs and advanced maternal age.

RESULTS

Compared with the 24 ≤ IPI ≤ 59 months group, the long IPI group (IPI ≥ 60 months) was associated with a higher risk of PTB (aOR, 1.27; 95% CI: 1.07-1.50), LBW (aOR, 1.32; 95% CI 1.08-1.61), and one-minute Apgar score ≤ 7 (aOR, 1.46; 95% CI 1.07-1.98). Negative additive interactions (all RERIs < 0) existed between long IPIs and advanced maternal age for these neonatal outcomes. Meanwhile, IPI < 12 months was also associated with PTB (aOR, 1.51; 95% CI 1.13-2.01), LBW (aOR, 1.50; 95% CI 1.09-2.07), and 1-min Apgar score ≤ 7 (aOR, 1.93; 95% CI 1.23-3.04).

CONCLUSIONS

Both short and long IPIs are associated with an increased risk of adverse neonatal outcomes. Appropriate IPI should be recommended to women planning to become pregnant again. In addition, better antenatal care might be taken to balance the inferiority of advanced maternal age and to improve neonatal outcomes.

Birth spacing and risk of adverse pregnancy and birth outcomes: A systematic review and dose-response meta-analysis

INTRODUCTION

The association between extreme birth spacing and adverse outcomes is controversial, and available evidence is fragmented into different classifications of birth spacing.

MATERIAL AND METHODS

We conducted a systematic review of observational studies to evaluate the association between birth spacing (i.e., interpregnancy interval and interoutcome interval) and adverse outcomes (i.e., pregnancy complications, adverse birth outcomes). Pooled odds ratios (ORs) with 95% confidence intervals (CI) were calculated using a random-effects model, and the dose-response relationships were evaluated using generalized least squares trend estimation.

RESULTS

A total of 129 studies involving 46 874 843 pregnancies were included. In the general population, compared with an interpregnancy interval of 18-23 months, extreme intervals (<6 months and ≥ 60 months) were associated with an increased risk of adverse outcomes, including preterm birth, small for gestational age, low birthweight, fetal death, birth defects, early neonatal death, and premature rupture of fetal membranes (pooled OR range: 1.08-1.56; p < 0.05). The dose-response analyses further confirmed these J-shaped relationships (pnon-linear  < 0.001-0.009). Long interpregnancy interval was only associated with an increased risk of preeclampsia and gestational diabetes (pnon-linear  < 0.005 and pnon-linear  < 0.001, respectively). Similar associations were observed between interoutcome interval and risk of low birthweight and preterm birth (pnon-linear  < 0.001). Moreover, interoutcome interval of ≥60 months was associated with an increased risk of cesarean delivery (pooled OR 1.72, 95% CI 1.04-2.83). For pregnancies following preterm births, an interpregnancy interval of 9 months was not associated with an increased risk of preterm birth, according to dose-response analyses (pnon-linear  = 0.008). Based on limited evidence, we did not observe significant associations between interpregnancy interval or interoutcome interval after pregnancy losses and risk of small for gestational age, fetal death, miscarriage, or preeclampsia (pooled OR range: 0.76-1.21; p > 0.05).

CONCLUSIONS

Extreme birth spacing has extensive adverse effects on maternal and infant health. In the general population, interpregnancy interval of 18-23 months may be associated with potential benefits for both mothers and infants. For women with previous preterm birth, the optimal birth spacing may be 9 months.

Proximate and distant determinants of maternal and neonatal mortality in the postnatal period: A scoping review of data from low- and middle-income countries

Global maternal and neonatal mortality rates remain unacceptably high. The postnatal period, encompassing the first hour of life until 42 days, is critical for mother-baby dyads, yet postnatal care (PNC) coverage is low. Identifying mother-baby dyads at increased risk for adverse outcomes is critical. Yet few efforts have synthesized research on proximate and distant factors associated with maternal and neonatal mortality during the postnatal period. This scoping review identified proximate and distant factors associated with maternal and neonatal mortality during the postnatal period within low- and middle-income countries (LMICs). A rigorous, systematic search of four electronic databases was undertaken to identify studies published within the last 11 years containing data on risk factors among nationally representative samples. Results were synthesized narratively. Seventy-nine studies were included. Five papers examined maternal mortality, one focused on maternal and neonatal mortality, and the rest focused on neonatal mortality. Regarding proximate factors, maternal age, parity, birth interval, birth order/rank, neonate sex, birth weight, multiple-gestation, previous history of child death, and lack of or inadequate antenatal care visits were associated with increased neonatal mortality risk. Distant factors for neonatal mortality included low levels of parental education, parental employment, rural residence, low household income, solid fuel use, and lack of clean water. This review identified risk factors that could be applied to identify mother-baby dyads with increased mortality risk for targeted PNC. Given risks inherent in pregnancy and childbirth, adverse outcomes can occur among dyads without obvious risk factors; providing timely PNC to all is critical. Efforts to reduce the prevalence of risk factors could improve maternal and newborn outcomes. Few studies exploring maternal mortality risk factors were available; investments in population-based studies to identify factors associated with maternal mortality are needed. Harmonizing categorization of factors (e.g., age, education) is a gap for future research.

Interpregnancy interval and the risk of oppositional defiant disorder in offspring

The study aimed to investigate the association between interpregnancy interval (IPI) and parent-reported oppositional defiant disorder (ODD) in offspring at 7 and 10 years of age. We used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), an ongoing population-based longitudinal study based in Bristol, United Kingdom (UK). Data included in the analysis consisted of more than 3200 mothers and their singleton children. The association between IPI and ODD was determined using a series of log-binomial regression analyses. We found that children of mothers with short IPI (<6 months) were 2.4 times as likely to have a diagnosis of ODD at 7 and 10 years compared to mothers with IPI of 18-23 months (RR = 2.45; 95%CI: 1.24-4.81 and RR = 2.40; 95% CI: 1.08-5.33), respectively. We found no evidence of associations between other IPI categories and risk of ODD in offspring in both age groups. Adjustment for a wide range of confounders, including maternal mental health, and comorbid ADHD did not alter the findings. This study suggests that the risk of ODD is higher among children born following short IPI (<6 months). Future large prospective studies are needed to elucidate the mechanisms explaining this association.

Association between interpregnancy interval and maternal and neonatal adverse outcomes in women with a cesarean delivery: a population-based study

BACKGROUND

Interpregnancy interval (IPI) has been linked with several maternal and neonatal adverse events in the general population. However, the association between IPI and maternal and neonatal outcomes in women whose first delivery was by cesarean delivery is unclear. We aimed to investigate the association between IPI after cesarean delivery and the risk of maternal and neonatal adverse events.

METHODS

Women (aged ≥ 18 years) whose first delivery was cesarean delivery with 2 consecutive singleton pregnancies from the National Vital Statistics System (NVSS) database between 2017 and 2019 were included in this retrospective cohort study. In this post-hoc analysis, logistic regression analyses were used to examine IPI (≤ 11, 12-17, 18-23 [reference], 24-35, 36-59, and ≥ 60 months) in relation to the risk of repeat cesarean delivery, maternal adverse events (maternal transfusion, ruptured uterus, unplanned hysterectomy, and admission to an intensive care unit), and neonatal adverse events (low birthweight, premature birth, Apgar score at 5 min < 7, and abnormal conditions of the newborn). Stratified analysis based on age (< 35 and ≥ 35 years) and previous preterm birth.

RESULTS

We included 792,094 maternities, 704,244 (88.91%) of which underwent a repeat cesarean delivery, 5,246 (0.66%) women had adverse events, and 144,423 (18.23%) neonates had adverse events. After adjusting for confounders, compared to an IPI of 18-23 months, the IPI of ≤ 11 months [odds ratio (OR) = 1.55, 95% confidence interval (CI): 1.44-1.66], 12-17 months (OR = 1.38, 95%CI: 1.33-1.43), 36-59 months (OR = 1.12, 95%CI: 1.10-1.15), and ≥ 60 months (OR = 1.19, 95%CI: 1.16-1.22) were associated with an increased risk of repeat cesarean delivery. In terms of maternal adverse events, only IPI of ≥ 60 months (OR = 0.85, 95%CI: 0.76-0.95) was observed to be associated with decreased risk of maternal adverse events in women aged < 35 years. In analysis of neonatal adverse events, IPI of ≤ 11 months (OR = 1.14, 95%CI: 1.07-1.21), 12-17 months (OR = 1.07, 95%CI: 1.03-1.10), and ≥ 60 months (OR = 1.05, 95%CI: 1.02-1.08) were related to an increased risk of neonatal adverse events.

CONCLUSION

Both short and long IPI were associated with an increased risk of repeat cesarean delivery and neonatal adverse events, and women < 35 years may benefit from a longer IPI.

Determinants of short birth interval among child-bearing age women in the Gedeb Hasasa district of the West Arsi zone, Ethiopia

Background

Short birth intervals have been linked to higher rates of fetal loss, prenatal mortality, and poorer child survival. Therefore, for countries like Ethiopia that have a population policy intended at reducing fertility, understanding the level and factors influencing birth spacing is crucial in order to apply appropriate intervention. This study aimed to assess the prevalence and determinants of the short birth interval among child-bearing age women in the Gedeb Hasasa district of the West Arsi zone, Ethiopia.

Methods

A community-based cross-sectional study was conducted from 20 July to 20 August 2018. A multistage sampling method was used. Face-to-face interviews were conducted to gather data. The collected data were entered into Epi Data version 3.1 and later exported to SPSS version 21 for analysis. Logistic regression was used to identify factors associated with the short birth interval. The level of significance was declared at a p-value of <0.05.

Results

A total of 714 women participated, with a 98% response rate. The median birth interval length was 32 months. The prevalence of the short birth interval was 50.4%. After adjusting for confounding variables, being a rural resident [AOR = 2.50, 95% CI (1.52, 4.09)], having an illiterate husband [AOR = 4.14, 95% CI (2.15, 8.45)], breastfeeding duration for 7-12 months [AOR = 3.16, 95% CI (1.95, 5.13)] and 13-23 months [AOR = 2.45, 95% CI (1.52, 3.95)], sex of the prior child [AOR = 0.63, 95% CI (0.45, 0.88)], and previous child alive [AOR = 0.20, 95% CI (0.14, 0.96)] were the determinants of short birth interval.

Conclusion and recommendation

One in every two women practiced short birth intervals. The median birth interval duration was 32 months, which is below the minimum standard recommended by the WHO duration for the birth interval, which is 33 months. Short birth intervals were determined independently by residence, husband education, breastfeeding time, previous child's sex, and previous child's survival. Therefore, increasing women's awareness of the ideal birth interval should be done through community health professionals and health developmental armies.

Interpregnancy interval and maternal and neonatal morbidity: a nationwide cohort study

This study aimed to assess the association between interpregnancy interval (IPI)-the time from childbirth to conception of the next pregnancy-and maternal and neonatal morbidity. The World Health Organization (WHO) currently recommends an IPI of at least 24 months after a live birth to reduce adverse birth outcomes. However, assessing the relationship between IPI and perinatal outcome is complicated by confounding factors. We conducted a nationwide population-based cohort study using Swedish registry data, allowing for adjustment of maternal characteristics and health at first birth. The study population consisted of all women with a singleton, live, and vaginal first birth with a second singleton birth within five years during 1997-2017, covering 327,912 women and 655,824 neonates. IPI was grouped into six-month intervals with 24-29 months as the reference. The association between IPI and morbidity was examined using multivariate logistic regression. For women having a vaginal delivery at their first birth, intervals < 24-29 months were associated with decreased maternal morbidity and unaffected neonatal morbidity. Intervals > 24-29 months were associated with increased maternal and neonatal morbidity. Our findings question the relevance of WHO's recommendation of an IPI of at least 24 months in a high-income country.

The effect of interpregnancy interval on preterm birth and low birth weight in singleton pregnancies conceived without assistance or by infertility treatments

OBJECTIVE

To determine the association of interpregnancy interval on perinatal outcomes and whether this was influenced by mode of conception.

DESIGN

Retrospective cohort.

SETTING

Centers for Disease Control and Prevention's natality national database.

PATIENT(S)

Patients who had an index singleton live birth with a preceding live birth. Index pregnancies from 2016 to 2019 were conceived with in vitro fertilization (IVF) (n = 32,829) or ovulation induction/intrauterine insemination (OI/IUI) (n = 23,016) or without assistance (n = 7,564,042).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcomes evaluated were preterm birth (<37 weeks) and low birth weight (<2,500 g). Multivariable logistic regression was performed to evaluate the association of interpregnancy intervals with perinatal outcomes stratified by mode of conception. Adjusted odds ratios and 95% confidence intervals (CIs) were presented.

RESULT(S)

Compared with the interpregnancy interval reference group of 12 to <18 months, a <12 month interpregnancy interval was associated with an increase in preterm birth (<37 weeks) for pregnancies conceived with OI/IUI or without assistance (aOR, 1.42; 95% CI, 1.16-1.74, and aOR, 1.14; 95% CI, 1.13-1.15, respectively), whereas IVF was not associated with an increase (aOR, 0.90; 95% CI, 0.77-1.04). A <12 month interpregnancy interval was associated with an increase in low birth weight for pregnancies conceived with IVF or OI/IUI or without assistance (aOR, 1.34; 95% CI, 1.09-1.64; aOR, 1.33; 95% CI, 1.01-1.76; and aOR, 1.26; 95% CI, 1.24-1.27, respectively).

CONCLUSION(S)

An interpregnancy interval of at least 12 months reduces adverse perinatal outcomes for pregnancies conceived with and without infertility treatment.

Interpregnancy interval and subsequent perinatal risk of congenital heart disease in Guangzhou, Southern China: a retrospective cohort study, 2014-2019

BACKGROUND

The association between maternal interpregnancy interval (IPI) and congenital heart disease (CHD) in neonates remains inconclusive. This study aimed to examine the effect of maternal IPI on birth risk of CHD.

METHODS

Chinese women with two consecutive singleton deliveries in Guangzhou between January 2014 and December 2019 were selected as participants. Information on IPI and CHD was extracted from the Guangzhou Perinatal Health Care and Delivery Registry and the Guangzhou Birth Defects Surveillance Program. We stratified IPI into four categories: <24 months, 24-35 months, 36-59 months, and ≥60 months. A multivariate logistic regression model was used to examine the association between IPI and CHD. Subgroup analysis was also performed to assess whether the associations differed across top three CHD subtypes.

RESULTS

For 119,510 women enrolled in this study, the mean ages at two consecutive deliveries were 26.2 ± 3.8 and 28.8 ± 4.0 years, which yielded a median IPI of 51.2 (interquartile range, 32.1-77.2) months. Among them, 828 delivered infants with CHD during their second pregnancy. There was a J-shaped curve relationship between IPI and CHD with the lowest birth prevalence (5.33‰) at 24-35-month interval. Compared to women with an IPI of 24-35 months, those with an IPI ≥60 had an increased risk of delivering infants with CHD (adjusted odds ratio (OR), 1.41; 95% confidence interval (CI), 1.19-1.64). However, for those with an IPI <24 months (adjusted OR, 1.24; 95% CI, 0.97-1.51), IPI was statistically insignificant associated with the risk of delivering infants with CHD (p = .12). There were different patterns of associations for different CHD subtypes.

CONCLUSIONS

Longer maternal IPI (≥60 months) was associated with an increased risk of delivering infants with CHD in the Chinese population.

Interpregnancy interval and hypertensive disorders of pregnancy: A population-based cohort study

BACKGROUND

Despite extensive research on risk factors and mechanisms, the extent to which interpregnancy interval (IPI) affects hypertensive disorders of pregnancy in high-income countries remains unclear.

OBJECTIVES

To examine the association between IPI and hypertensive disorders of pregnancy in a high-income country setting using both within-mother and between-mother comparisons.

METHODS

A retrospective population-based cohort study was conducted among 103 909 women who delivered three or more consecutive singleton births (n = 358 046) between 1980 and 2015 in Western Australia. We used conditional Poisson regression with robust variance, matching intervals of the same mother and adjusted for factors that vary within-mother across pregnancies, to investigate the association between IPI categories (reference 18-23 months), and the risk of hypertensive disorders of pregnancy. For comparison with previous studies, we also applied unmatched Poisson regression (between-mother analysis).

RESULTS

The incidence of preeclampsia and gestational hypertension during the study period was 4%, and 2%, respectively. For the between-mother comparison, mothers with intervals of 6-11 months had lower risk of preeclampsia with adjusted relative risk (RR) 0.92 (95% confidence interval [CI] 0.85, 0.98) compared to reference category of 18-23 months. With the within-mother matched design, we estimated a larger effect of long IPI on risk of preeclampsia (RR 1.29, 95% CI 1.18, 1.42 for 60-119 months; and RR 1.30, 95% CI 1.10, 1.53 for intervals ≥120 months) compared to 18-23 months. Short IPIs were not associated with hypertensive disorders of pregnancy.

CONCLUSIONS

In our cohort, longer IPIs were associated with increased risk of preeclampsia. However, there was insufficient evidence to suggest that short IPIs (<6 months) increase the risks of hypertensive disorders of pregnancy.

Association of Short and Long Interpregnancy Intervals with Adverse Birth Outcomes: Evidence from a Cross-Sectional Study in Northwest China

Purpose

To analyze the effects of a short interpregnancy interval (IPI) (<6 months) and a long IPI (>120 months) on neonatal adverse birth outcomes including low birth weight (LBW), small for gestational age (SGA), preterm birth (PTB), and birth defects in Shaanxi Province.

Patients and Methods

A stratified multistage random sampling method was used to recruit participants who gave birth between 2010 and 2013 in Shaanxi province. A self-designed questionnaire was used to collect the information of the participants. With the confounding factors controlled, the generalized linear model (GLM) was used to investigate the association between IPI and neonatal birth outcomes. The restricted cubic spline (RCS) function was used to evaluate the dose–response relationship between IPI and birth outcomes.

Results

A total of 13,231 women were included. The prevalence of LBW, SGA, PTB, and birth defects was 3.24%, 12.96%, 2.93%, and 2.12%, respectively. GLM showed that a short IPI (<6 months) was associated with a higher risk of SGA (RR=1.25, 95% CI: 1.04–1.52) and birth defects (RR=2.55, 95% CI: 1.45–4.47), and a long IPI (≥120 months) was associated with a higher risk of LBW (RR=1.54, 95% CI: 1.01–2.34) and PTB (RR=1.73, 95% CI: 1.08–2.76) than an IPI of 18–23 months. The RCS showed that LBW, SGA, and PTB demonstrated a j-shaped relationship with IPI (P for overall association < 0.001 for these three birth outcomes), and birth defects (P for overall association <0.001) had an inversely non-linear relationship with IPI.

Conclusion

Both short and long IPIs are associated with an increased risk of adverse birth outcomes.

Association between maternal iron supplementation and newborn birth weight: a quantile regression analysis

Objective

Our study aimed to explore the association between maternal iron supplementation and newborn birth weight (BW) in Shaanxi Province using quantile regression (QR).

Method

The data used in this study were derived from a large cross-sectional survey of a population in Shaanxi Province, Northwest China. A total of 28,209 women and their infants were selected using a stratified multistage random sampling method. The effect of iron supplementation on the newborn BW was assessed by a multiple linear regression model and QR.

Results

A total of 5.15% of the women took iron supplements during pregnancy. Multiple linear regression showed that the iron supplementation during pregnancy had positive effects on the BW, with an average increase of 43.07 g (β = 43.07, t = 3.55, and p < 0.001). The QR showed that the iron supplementation during pregnancy was associated with an increased newborn BW from very low to higher percentiles (quantiles: 0 ~ 0.40), with the β ranging from 136.51 to 43.86. As the percentiles of the BW increased, the neonatal BW gain gradually declined in the iron supplementation group compared with the group that did not receive iron supplementation (quantiles: 0 ~ 0.40, with the β ranging from 136.51 to 43.86). Iron supplementation was more effective among women who suffered from anemia during pregnancy (β = 45.84, t = 2.05, and p = 0.04; quantiles: 0 ~ 0.15, 0.30, 0.80, with β ranging from 150.00 to 39.29) than it was in any other group (β = 38.18, t = 2.62, and p = 0.009; quantiles: 0 ~ 0.15, with β ranging from 133.33 to 28.32).

Conclusions

Iron supplementation during pregnancy is associated with an increased newborn BW, and the effect was more obvious in the newborns with the lower BW and newborns whose mothers suffered from anemia during pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13052-021-01084-7.

The effect of short interpregnancy interval on birthweight and other pregnancy outcomes in Enugu, Southeast Nigeria

The time interval between one pregnancy and the next is a modifiable risk factor, and has an effect on pregnancy outcomes. This study compared the effects of short interpregnancy interval (IPI) on fetal birthweight and selected pregnancy outcomes amongst parturients in Enugu, Nigeria. Group A (Subjects) consisted of parturients with short IPI (IPI < 18 months), while group B (Controls) consisted of parturients with normal IPI (IPI ≥ 18 months). Relevant obstetric data were collected at delivery. Mean birthweight was 2664.13 ± 339.25g vs 3670.63 ± 452.69g in women with short IPI and normal IPI respectively (p < .0001). Women with short IPI were more likely to have low birthweight babies compared to those with normal IPI (OR = 7.331, p < .001). Maternal anaemia, preeclampsia and caesarean delivery were significantly more associated with short IPI. Women with short IPI are at greater risk of delivering newborn babies with significantly lower mean birthweight and other associated pregnancy complications than women with normal IPI.Impact StatementWhat is already known on this subject? Short interpregnancy interval has an adverse effect on pregnancy outcomes as shown in studies from Europe and the Americas.What do the results of this study add? This study adds to the body of evidence of the deleterious effects of inadequately spaced pregnancies and draws attention to this in West Africa, sub-Saharan Africa, and an area with low contribution to studies on the effect of short IPI on pregnancy outcomes.What are the implications of these findings for clinical practice and/or further research? With evidence from our own environment, it will further boost evidence for proper education of our mothers on the need for adequate birth spacing to avoid the adverse effects of a short IPI on the next pregnancy.

The interval between births and the risk of recurrent preeclampsia among predominantly high risk women in urban tertiary care center

INTRODUCTION

Women with a history of preeclampsia have a higher risk of recurrent preeclampsia. This study sought to ascertain the relationship between the interbirth interval and the risk of recurrent preeclampsia and difference in angiogenic markers between the two groups.

METHODS

Data was collected from an ongoing cohort study of women with hypertensive disorders of pregnancy (HDP) enrolled at the admission to the labor and delivery floor. From this dataset, multigravida women with a prior diagnosis of preeclampsia were identified and compared to women with no prior history of preeclampsia.

RESULTS

Of the 375 women with HDP who were predominantly African American, 245 were multigravida and 44 (18.0%) had a prior history of preeclampsia. Women with prior preeclampsia had an earlier gestational age of delivery, higher rates of preterm delivery and a higher incidence of preeclampsia with severe features (56.8% vs 29.8%) in the index pregnancy (p-values ≤ 0.001) than those without. The median number of years between history of preeclampsia in previous pregnancy and current pregnancy was 6 years (IQR 3, 8). Among patients with a prior history of preeclampsia, the interbirth interval was not associated with severe preeclampsia (p = 0.60) and there was no difference in angiogenic factors between patients with a prior history of preeclampsia compared to those without.

CONCLUSIONS

In this study, the duration of the interbirth interval was not identified as a risk factor of developing severe preeclampsia in a subsequent pregnancy and angiogenic factors are not a reflection of maternal predisposition to recurrent preeclampsia.

A population-based study of preeclampsia and eclampsia in Ecuador: ethnic, geographical and altitudes differences

Background

In Ecuador eclampsia and preeclampsia were identified as the third cause of maternal death. Like other Latin-American countries, Ecuador has human settlements living from 0 to more than 4000 m of altitude and comprising a wide ethnic-diversity across all these altitude changes. These characteristics offer the possibility to study a wide variety of possible risk factors for preeclampsia and eclampsia.

Methods

We conducted a population-based retrospective study of all deliveries in Ecuador from 2015 through 2017. The main variables analyzed were: altitude, ethnic self-identification, geographic location, and maternal age. The data comes from the Ecuadorian National Institute of Statistics and Census (INEC) and the Ecuadorian Ministry of Health. Data information regarding maternal parity and socioeconomic status was not available from official records. Logistic regression analysis was used to study the relationship between preeclampsia and eclampsia with the variable of interest. Geospatial statistical analysis was done to identify statistically significant spatial clusters of preeclampsia and eclampsia cases.

Results

The incidence of preeclampsia was estimated between 5.11 (5.05–5.18) and 6.23 (6.16–6.30), and 0.25 (0.23–0.26) for eclampsia. Native American have a lower incidence regarding preeclampsia compared to other ethnic groups. High altitude has a significant odds ratio (OR = 2.31, 1.93–2.78) of preeclampsia. Montubio residing in middle altitude (1500–3500 m) have the highest risk of preeclampsia (OR = 18.13, 9.53–34.50). Afro-Ecuadorians also have an increased risk of preeclampsia associated with altitude (OR = 2.36, 1.78–3.14). Ethnicity was not identified as a risk factor for eclampsia. Early and older maternal age was associated with an increased risk of preeclampsia and eclampsia. Women living more than 20 km from the obstetric unit have an OR = 2.61 (2.32–2.95, p-value< 0.01) and OR = 1.87 (1.82–1.92, p-value< 0.01) of developing eclampsia and preeclampsia respectively.

Conclusions

Preeclampsia is widespread across low and high-altitude areas, while eclampsia is mostly located at lower altitudes. Montubios living at middle or high altitudes represents the ethnic group with a higher risk of preeclampsia. No ethnic effect was identified as a potential risk factor for eclampsia. Moreover, in eclampsia the associated risk of young women seems to be higher than in preeclampsia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03602-1.

Safety and Immunogenicity of a Second Dose of an Investigational Maternal Trivalent Group B Streptococcus Vaccine in Nonpregnant Women 4-6 Years After a First Dose: Results From a Phase 2 Trial

Background

Maternal immunization against group B streptococcus (GBS) could protect infants from invasive GBS disease. Additional doses in subsequent pregnancies may be needed. We evaluated the safety and immunogenicity of a second dose of an investigational trivalent CRM₁₉₇-glycoconjugate GBS vaccine (targeting serotypes Ia/Ib/III), administered to nonpregnant women 4–6 years postdose 1.

Methods

Healthy women either previously vaccinated with 1 dose of trivalent GBS vaccine 4–6 years before enrollment (n = 53) or never GBS vaccinated (n = 27) received a single trivalent GBS vaccine injection. Adverse events (AEs) were recorded. Serotype-specific (Ia/Ib/III) anti-GBS antibodies were measured by multiplex immunoassay prevaccination and 30/60 days postvaccination.

Results

AEs were reported with similar rates after a first or second dose; none were serious. Of previously GBS-vaccinated women, 92%–98% had anti-GBS concentrations that exceeded an arbitrary threshold (8 µg/mL) for each serotype 60 days postdose 2 vs 36%–56% postdose 1 in previously non–GBS-vaccinated women. Of previously GBS-vaccinated women with undetectable baseline (predose 1) anti-GBS levels, 90%–98% reached this threshold postdose 2. For each serotype, anti-GBS geometric mean concentrations (GMCs) 30/60 days postdose 2 in previously GBS-vaccinated women were ≥200-fold higher than baseline GMCs. Among women with undetectable baseline anti-GBS levels, postdose 2 GMCs in previously GBS-vaccinated women exceeded postdose 1 GMCs in previously non–GBS-vaccinated women (≥7-fold).

Conclusions

A second trivalent GBS vaccine dose administered 4–6 years postdose 1 was immunogenic with a favorable safety profile. Women with undetectable preexisting anti-GBS concentrations may benefit from a sufficiently spaced second vaccine dose.

Clinical Trials Registration

NCT02690181

Short interpregnancy interval and low birth weight births in India: Evidence from National Family Health Survey 2015-16

Evidence on the effect of interpregnancy interval (IPI) on low birth weight (LBW) births is limited in developing countries including India. Our study aims to examine association between IPI and LBW births in India. We used data from the fourth round of the National Family Health Survey (NFHS-4) conducted in 2015–16 with a representative sample of 52,825 most recent births for examining the association between IPI and LBW. IPI is defined as the gap between the first month in which the index pregnancy was reported in the reproductive calendar (referred to as the month of conception) and the month of pregnancy outcome (including live births and terminations) of preceding pregnancy. Reproductive calendar data were used to estimate IPI. Association between IPI and LBW were examined using multivariable binary logistic regressions. Seventeen percent of the births in our sample were LBW, and more than half (57.6%) of these were accompanied with IPI less than 18 months. Prevalence of LBW births was highest among mother's who had IPI less than six months (19.4%). Regression results, adjusted for control variables, indicate that the risk of LBW was significantly higher among births whose mothers had IPI less than six months (odds ratio: 1.19, 95% CI:1.05-1.36) compared with those whose mothers had IPI between 18 and 23 months. This study provides additional evidence on the association between short IPI (<6 months) and LBW births in India. Promoting spacing methods of family planning is an option that India may consider for increasing the IPI and thereby reducing LBW births. Ensuring recommended iron and folic acid tablets/equivalent syrup and TT injections for every pregnant woman may offset the adverse consequences of shorter IPI.

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12% of the LBW births were accompanied with IPI <6 months, 20% between 6 and 11 months, and 25% between 12 and 17 months.

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The risk of LBW births is higher among mothers having an IPI of <6 months compared with mothers having an IPI of 18–23 months.

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Promoting spacing methods of family planning may consider for increasing the IPI and thereby reducing LBW births in India.

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Promoting recommended TT injections and iron-folic acid supplements may offset the adverse consequences of short IPI.

Prolonged interpregnancy interval: how does it impact the length of second stage of labor?

Objectives Short interpregnancy intervals (IPI) have been linked to multiple adverse maternal and neonatal outcomes, but less is known about prolonged IPI, including its relationship with labor progression. The objective of the study was to investigate whether prolonged IPIs are associated with longer second stages of labor. Methods A perinatal database from Kaiser Permanente Hawaii was used to identify 442 women with a prolonged IPI ≥60 months. Four hundred forty two nulliparous and 442 multiparous women with an IPI 18-59 months were selected as comparison groups. The primary outcome was second stage of labor duration. Perinatal outcomes were compared between these groups. Results The median (IQR) second stage of labor duration was 76 (38-141) min in nulliparous women, 15 (9-28) min in multiparous women, and 18 (10-38) min in women with a prolonged IPI (p<0.0001). Pairwise comparisons revealed significantly different second stage duration in the nulliparous group compared to both the multiparous and prolonged IPI groups, but no difference between the multiparous and prolonged IPI groups. There was a significant association with the length of the IPI; median duration 30 (12-61) min for IPI ≥120 months vs. 15 (9-27) min for IPI 18-59 months and 16 (9-31) min for IPI 60-119 months (p=0.0014). Conclusions The second stage of labor did not differ in women with a prolonged IPI compared to normal multiparous women. Women with an IPI ≥120 months had a significantly longer second stage vs. those with a shorter IPI. These findings provide a better understanding of labor progression in pregnancies with a prolonged IPI.

Experience on Safety, Expulsion, and Complication of Intracesarean Post-Partum Intrauterine Copper Device

Background

The post-partum period is one of the critical times when ovulation is highly unpredictable and couples often underestimate the likelihood of pregnancy. According to the World Health Organization, intrauterine copper device (IUCD) can be inserted within 48 hours post-partum, referred to as post-partum IUCD (PPIUCD). The objectives of the present study were to determine the safety and expulsion of intracesarean PPIUCD. This study also has an objective to determine the complications (undescended/missed thread, bleeding, pain, and infection) following intracesarean PPIUCD insertion among the women.

Materials and methods

This was a prospective interventional hospital-based study conducted in the Department of Obstetrics & Gynecology, Uttar Pradesh University of Medical Sciences, Saifai, Etawah, Uttar Pradesh, India, from November 1, 2016, to October 31, 2019. Women were followed up at six weeks and six months for various objectives.

Results

Intracesarean PPIUCD was inserted in a total of 1,586 patients, and 1,029 cases came for follow-up at six weeks and six months; thus, the concluded sample size was 1,029. The majority of patients were of 20 to 25 years of age, belonged to rural areas, and were having parity 2. The most common complaint was of undescended/missed thread in 22.2% women followed by bleeding (11.9%), expulsion (2.2%), pain (2%), and local infection (1.3%) at six weeks follow-up. At six months, the most common complaint was missed thread in 8.6% followed by bleeding (6.0%), pain (1.6%), expulsion (1.2%), and local infection (0.7%). There was no case of perforation. While 19.05% women wanted the removal of PPIUCD, but at the end of the study period, it was removed in a total of 11.27% cases due to various reasons.

Conclusions

PPIUCD is an effective tool to reduce the unmet need of contraception. This study showed that most of the women were satisfied with the intracesarean insertion of IUCD, indicating its important place within the basket of post-partum family planning methods.

Interpregnancy interval and risk of perinatal death: a systematic review and meta-analysis

BACKGROUND

Interpregnancy interval (IPI) <6 months is a potentially modifiable risk factor for adverse perinatal health outcomes.

OBJECTIVE

This systematic review evaluated the international literature on the risk of perinatal death associated with IPI.

SEARCH STRATEGY

Two independent reviewers screened titles and abstracts identified in MEDLINE, EMBASE and Scopus from inception to 4 April 2019 (Prospero Registration #CRD42018092792).

SELECTION CRITERIA

Studies were included if they provided a description of IPI measurement and perinatal death, including stillbirth and neonatal death.

DATA COLLECTION AND ANALYSIS

A narrative review was performed for all included studies. Random effects meta-analysis was used to compare unadjusted odds of perinatal death associated with IPI <6 months and IPI ≥6 months. Analyses were performed by outcome of the preceding pregnancy and study location.

MAIN RESULTS

Of the 624 unique articles identified, 26 met the inclusion criteria. The pooled unadjusted odds ratio of perinatal death for IPI <6 months was 1.34 (95% CI 1.17-1.53) following a previous live birth, 0.85 (95% CI 0.73-0.99) following a previous miscarriage and 1.07 (95% CI 0.84-1.36) following a previous stillbirth compared with IPI ≥6 months. However, few high-income country studies reported an association after adjustment. Fewer studies evaluated the impact of long IPI on perinatal death and what evidence was available showed mixed results.

CONCLUSIONS

Results suggest a possible association between short IPI and risk of perinatal death following a live birth, particularly in low- to middle-income countries.

TWEETABLE ABSTRACT

Short IPI <6 months after a live birth was associated with greater risk of perinatal death than IPI ≥6 months.

Interpregnancy interval and the risk for recurrence of placental mediated pregnancy complications

Objective The aim of this study was to investigate the effect of short or long interpregnancy interval (IPI) with placental mediated pregnancy complications after already complicated first delivery. Methods We performed a retrospective cohort analysis of all women with singleton pregnancies who delivered their first three consecutive deliveries in one university-affiliated medical center (1994-2013). Placental mediated complications included placental abruption, small for gestational age, preeclampsia, gestational hypertension, or preterm delivery. Following first complicated delivery, IPI was compared stratified by second delivery outcome. Following two complicated deliveries, IPI was compared stratified by third delivery outcome. IPI was evaluated as continuous or categorical variable (>18, 18-60, >60 months). Related samples Cochrans' Q test and Mann-Whitney analysis were used as appropriate. Results Overall, 4310 women entered analysis. Of them, 18.3%, 10.5%, and 9.3% had complicated first, second, and third delivery, consecutively. Evaluated continuously, longer IPI, but not short IPI, was associated with higher rates of complicated second delivery. Stratified to categories, IPI had no effect on recurrent complications evaluated separately or as composite. Conclusion Our results suggest that long IPI may increase risk for placental mediated pregnancy complications. Further studies are needed to evaluate this effect.

Complex samples logistic regression analysis of predictors of the current use of modern contraceptive among married or in-union women in Sierra Leone: Insight from the 2013 demographic and health survey

BACKGROUND

Non-use of modern contraceptives among married or in-union women aged 15 to 49 years is a demographic and public health challenge. Studies on the predictors of contraceptive use among women in Sierra Leone are few, more than two decades old, and not nationally representative. This study aims to fill this gap by estimating the prevalence and the predictors of the current use of modern contraceptives among married or in-union women in Sierra Leone.

METHODS

This is a population-based study that used the 2013 Sierra Leone Demographic and Health Survey (SDHS) dataset. We performed complex samples logistic regression with 9,111 reproductive-age women. The analysis was done using the IBM SPSS Statistics version 21, and statistical significance was pegged at p≤0.01 and p≤0.05. The outcome of interest is the current use of modern contraceptives among reproductive-age married or in-union women in Sierra Leone, measured as 'Yes' (currently using a modern method) and 'No' (using a folkloric method, traditional method, and no method).

RESULTS

About 18.1% of reproductive-age women were currently using a modern contraceptive. The study found the following sociodemographic factors as positive correlates: being within the age group of 20-24 years [AOR = 1.52, CI: 1.05, 2.19], 25-29 years [AOR = 1.57, CI: 1.10, 2.19], 30-34 years [AOR = 2.31, CI: 1.59, 3.36], 35-39 years [AOR = 1.89, CI: 1.33, 2.70], 40-44 years [AOR = 1.68, CI: 1.12, 2.52], obtaining either a primary [AOR = 1.40, CI: 1.14, 1.71] or secondary level education [AOR = 1.34, CI: 1.02, 1.74], belonging to the category of women that condemned wife beating under only one condition [AOR = 1.37, CI: 1.03, 1.78], under two conditions [AOR = 1.45, CI: 1.08, 1.93], under three conditions [AOR = 1.73, CI: 1.28, 2.35], under four conditions [AOR = 1.91, CI: 1.34, 2.72], and under five conditions [AOR = 1.41, CI: 1.07, 1.85], having the ability to refuse sex [AOR = 1.46, CI: 1.23, 1.76], ever heard family planning on the radio [AOR = 1.30, CI: 1.08, 1.58], being sexually active four weeks prior to the survey [AOR = 3.90, CI: 3.14, 4.84], ever taken an HIV test [AOR = 1.67, CI: 1.39, 2.02], ever visited a health facility in the last 12 months [AOR = 1.73, CI: 1.44, 2.09], dwelling in a richer household [AOR = 1.32, CI: 1.01, 1.72], and dwelling in an urban area [AOR = 1.44, CI: 1.14, 1.81]. Exposure to family planning through print media (newspaper/magazine) was negatively associated with current use of modern contraceptive [AOR = 0.60, CI: 0.37, 0.96].

CONCLUSION

The study provided in-depth insight into the sociodemographic predictors of the current use of modern contraceptives among married or in-union women in Sierra Leone. The study underscored the need to promote the protective factors of the current use of modern contraceptives and address the risk factors of the low prevalence of modern contraceptive use through policies, programs, and interventions in Sierra Leone.

Association between long interpregnancy intervals and cesarean delivery due to arrest disorders

BACKGROUND

It is hypothesized that pregnancy causes time-limited physiologic adaptations of the reproductive system, such as increased blood flow to the uterus. With long interpregnancy intervals, those adaptations may regress, and maternal physiologic characteristics may revert to those of primigravid women. Therefore, it is plausible that long interpregnancy interval is associated with cesarean delivery, especially due to arrest disorders (failed induction of labor, arrest of dilation, or arrest of descent).

OBJECTIVE

To examine the association between interpregnancy interval and cesarean delivery due to arrest disorders in multiparous women without a history of cesarean delivery.

MATERIALS AND METHODS

This was a retrospective cohort study of all women who had more than 1 singleton pregnancy at 23 weeks' gestation or greater at MedStar Washington Hospital Center from January 2009 to June 2018. We defined the interpregnancy interval as the duration from the birth of the preceding offspring to the date of conception of the index offspring. We a priori decided to categorize women based on the interpregnancy interval (less than 18 months, 18-59 months, and 60 months or greater). Our primary outcome was cesarean delivery due to arrest disorders. We also examined overall cesarean delivery and cesarean delivery due to nonreassuring fetal heart tracing. Multivariable logistic regression was performed to calculate adjusted odds ratios and 95% confidence intervals, controlling for predefined covariates.

RESULTS

Of 2741 women, 1143 (41.7%), 1369 (49.9%), and 229 (8.4%) had an interpregnancy interval of less than 18 months, 18-59 months, and 60 months or more, respectively. After adjusting for confounders, an interpregnancy interval of 60 months or more compared to an interpregnancy interval of 18-59 months was associated with increased odds of cesarean delivery due to arrest disorders (4.8% vs 1.3%; adjusted odds ratio, 3.06; 95% confidence interval, 1.34-6.97) and cesarean delivery due to arrest of dilation (3.1% vs 0.7%; adjusted odds ratio, 3.24; 95% confidence interval, 1.10-9.59). An interpregnancy interval of less than 18 months compared to an interpregnancy interval of 18-59 months was associated with decreased odds of cesarean delivery due to nonreassuring fetal heart tracing (2.4% vs 4.1%; adjusted odds ratio, 0.55; 95% confidence interval, 0.32-0.92).

CONCLUSION

An interpregnancy interval of 60 months or greater compared to an interpregnancy interval of 18-59 months was associated with increased odds of cesarean delivery due to arrest disorders. Beneficial effects on postpartum adaptations in the reproductive system may regress as interpregnancy interval increases.

Long interpregnancy interval and adverse perinatal outcomes: A retrospective cohort study

We conducted a retrospective cohort study of 9,552 women experiencing their second delivery between 2014 and 2016 at the International Peace Maternity and Child Health Hospital to investigate the association between the interpregnancy interval (IPI) and adverse perinatal outcomes. With the 12-23-mon IPI as the reference category, logistic regression analyzes were used to examine associations between different IPIs (<12, 12-23, 24-59, 60-119, and ≥120 mon) and perinatal outcomes (gestational diabetes mellitus, premature membrane rupture, gestational hypertension, preterm birth, low birth weight, and macrosomia). Compared with the 12-23-mon IPI category, women with longer IPIs had a higher risk of adverse perinatal outcomes, and those with an IPI ≥120 mon had the highest risk of gestational diabetes mellitus and premature membrane rupture (adjusted odds ratio (OR) 1.76, 95% confidence interval (CI) 1.32-2.35 and adjusted OR 2.03, 95% CI 1.53-2.67, respectively). These results indicate that a longer IPI is associated with a higher risk of adverse perinatal outcomes and an IPI of ≥120 mon appears to be independently associated with a higher risk of gestational diabetes mellitus and premature membrane rupture.

Examining internal migration effects on short versus long interbirth intervals in Cotonou, Benin Republic

Background

The literature on migration-fertility relationship uses various measures of fertility, such as fertility rates, actual fertility and family size preferences. This study introduces a different measure—interbirth intervals over women’s reproductive years—to examine how internal migration is associated with short interbirth intervals (less than 24 months) and long interbirth intervals (greater than 60 months) in Cotonou, the largest city of Benin Republic.

Methods

The paper uses primary data on 2852 live births to 1659 women aged 15–49 years from the 2018 Fertility and Migration Survey in Cotonou. Competing-risks models were fitted for the analysis.

Results

Nineteen percent of live births were of short interbirth intervals and 16% were of long interbirth intervals. The prevalence of short interbirth intervals was higher among migrants who spent less than 5 years in Cotonou (29%) than among non-migrants (19%) and earlier migrants (18%). Non-migrants had the highest proportion of long interbirth intervals (19%). Within the first 5 years following the migration to Cotonou, migrants had higher subhazard ratio (SHR) of short interbirth intervals (SHR: 1.71, 95% CI: 1.33–2.21) and lower SHR of long interbirth intervals (SHR: 0.64, 95% CI: 0.47–0.87) than non-migrants. This association holds after controlling for socioeconomic characteristics—but with a slightly reduced gap between migrants who spent less than 5 years in Cotonou and non-migrants. Afterwards and irrespective of women’s socioeconomic backgrounds, migrants who spent 5 or more years in Cotonou and non-migrants had similar risks of short and long interbirth intervals. Finally, from 5 years of stay in Cotonou, migrants for reasons other than school or job were less likely to experience short interbirth intervals (SHR: 0.65, 95% CI: 0.46–0.98 for migrants who spent 5–10 years in Cotonou, and SHR: 0.74, 95% CI: 0.54–1.02 for migrants who spent more than 10 years in Cotonou) than non-migrants.

Conclusion

Family planning programmes should mainly target migrants in the early years after their arrival in Cotonou. Moreover, non-migrants need to be sensitised on the adverse health outcomes of long interbirth intervals.

Interpregnancy intervals and women's knowledge of the ideal timing between birth and conception

BACKGROUND

Short interpregnancy intervals (IPIs) are associated with adverse obstetric outcomes. However, few studies have explored women's understanding of ideal IPIs or investigated knowledge of the consequences of short IPIs.

METHODS

We performed a prospective questionnaire-based study at two hospitals in Sydney, Australia. We recruited women attending antenatal clinics and collected demographic data, actual IPI, ideal IPI, contraceptive use, and education provided on birth-spacing and contraception following a previous live birth. We explored associations between an IPI <12 months and a selection of demographic and health variables.

RESULTS

Data were collected from 467 women, of whom 344 were pregnant following a live birth. Overall, 72 (20.9%) women had an IPI <12 months only 7.5% of whom believed this was ideal, and the remaining stating their ideal IPI was over 12 months (52.3%) or they had no ideal IPI (40.3%). IPI <12 months following a live birth was significantly associated with younger age (p=0.043) but not with ethnicity, relationship status, education, religion, parity nor previous mode of delivery. IPI <12 months was associated with non-use of long-acting reversible contraception (LARC) (p<0.001), breastfeeding <12 months (p=0.041) and shorter ideal IPI (p=0.03). Less than half of the women (43.3%, n=149) reported having received advice about IPI and less than half about postnatal contraception (44.2%, n=147).

CONCLUSIONS

Younger age and non-use of LARC are significantly associated with IPIs <12 months. A minority of women with a short IPI perceived it to be ideal. Prevention of short IPIs could be achieved with improved access to postnatal contraception.

The effect of short pregnancy interval on perinatal outcomes in Turkey: A retrospective study

OBJECTIVE

The aim of the study was to determine the effect of short pregnancy interval on perinatal outcomes.

METHODS

The research was a retrospective study. The material consisted of birth records of a state hospital for the last three years in Manisa in the western region of Turkey (2015-2017) (n:8961). The research population included women whose gestational interval was ≤two years and the gestational week was over 22 weeks (n:2089). Perinatal outcomes were assessed through preterm birth, stillbirth, and low birth weight.

RESULTS

The mean age of women who are in the research group is 26.7 ± 5.32. According to the perinatal results of women with a pregnancy interval of two years and shorter; 8.2% of women had birth before 37 weeks and 0.3% resulted in stillbirth. It was determined that 4.8% of infants were born with low birth weight. There was no difference between the short pregnancy interval and stillbirth or preterm birth. However, a significant difference was found between the low birth weight and short pregnancy interval. (p>0.05).

CONCLUSIONS

Pregnancy interval does not affect preterm birth and stillbirth from perinatal outcomes, but has a significant effect on the birth weight of the newborn.

The International Federation of Gynecology and Obstetrics (FIGO) initiative on pre-eclampsia: A pragmatic guide for first-trimester screening and prevention

Pre‐eclampsia (PE) is a multisystem disorder that typically affects 2%–5% of pregnant women and is one of the leading causes of maternal and perinatal morbidity and mortality, especially when the condition is of early onset. Globally, 76 000 women and 500 000 babies die each year from this disorder. Furthermore, women in low‐resource countries are at a higher risk of developing PE compared with those in high‐resource countries. Although a complete understanding of the pathogenesis of PE remains unclear, the current theory suggests a two‐stage process. The first stage is caused by shallow invasion of the trophoblast, resulting in inadequate remodeling of the spiral arteries. This is presumed to lead to the second stage, which involves the maternal response to endothelial dysfunction and imbalance between angiogenic and antiangiogenic factors, resulting in the clinical features of the disorder. Accurate prediction and uniform prevention continue to elude us. The quest to effectively predict PE in the first trimester of pregnancy is fueled by the desire to identify women who are at high risk of developing PE, so that necessary measures can be initiated early enough to improve placentation and thus prevent or at least reduce the frequency of its occurrence. Furthermore, identification of an “at risk” group will allow tailored prenatal surveillance to anticipate and recognize the onset of the clinical syndrome and manage it promptly. PE has been previously defined as the onset of hypertension accompanied by significant proteinuria after 20 weeks of gestation. Recently, the definition of PE has been broadened. Now the internationally agreed definition of PE is the one proposed by the International Society for the Study of Hypertension in Pregnancy (ISSHP). According to the ISSHP, PE is defined as systolic blood pressure at ≥140 mm Hg and/or diastolic blood pressure at ≥90 mm Hg on at least two occasions measured 4 hours apart in previously normotensive women and is accompanied by one or more of the following new‐onset conditions at or after 20 weeks of gestation: 1.Proteinuria (i.e. ≥30 mg/mol protein:creatinine ratio; ≥300 mg/24 hour; or ≥2 + dipstick); 2.Evidence of other maternal organ dysfunction, including: acute kidney injury (creatinine ≥90 μmol/L; 1 mg/dL); liver involvement (elevated transaminases, e.g. alanine aminotransferase or aspartate aminotransferase >40 IU/L) with or without right upper quadrant or epigastric abdominal pain; neurological complications (e.g. eclampsia, altered mental status, blindness, stroke, clonus, severe headaches, and persistent visual scotomata); or hematological complications (thrombocytopenia–platelet count <150 000/μL, disseminated intravascular coagulation, hemolysis); or 3.Uteroplacental dysfunction (such as fetal growth restriction, abnormal umbilical artery Doppler waveform analysis, or stillbirth). It is well established that a number of maternal risk factors are associated with the development of PE: advanced maternal age; nulliparity; previous history of PE; short and long interpregnancy interval; use of assisted reproductive technologies; family history of PE; obesity; Afro‐Caribbean and South Asian racial origin; co‐morbid medical conditions including hyperglycemia in pregnancy; pre‐existing chronic hypertension; renal disease; and autoimmune diseases, such as systemic lupus erythematosus and antiphospholipid syndrome. These risk factors have been described by various professional organizations for the identification of women at risk of PE; however, this approach to screening is inadequate for effective prediction of PE. PE can be subclassified into: 1.Early‐onset PE (with delivery at <34+0 weeks of gestation); 2.Preterm PE (with delivery at <37+0 weeks of gestation); 3.Late‐onset PE (with delivery at ≥34+0 weeks of gestation); 4.Term PE (with delivery at ≥37+0 weeks of gestation). These subclassifications are not mutually exclusive. Early‐onset PE is associated with a much higher risk of short‐ and long‐term maternal and perinatal morbidity and mortality. Obstetricians managing women with preterm PE are faced with the challenge of balancing the need to achieve fetal maturation in utero with the risks to the mother and fetus of continuing the pregnancy longer. These risks include progression to eclampsia, development of placental abruption and HELLP (hemolysis, elevated liver enzyme, low platelet) syndrome. On the other hand, preterm delivery is associated with higher infant mortality rates and increased morbidity resulting from small for gestational age (SGA), thrombocytopenia, bronchopulmonary dysplasia, cerebral palsy, and an increased risk of various chronic diseases in adult life, particularly type 2 diabetes, cardiovascular disease, and obesity. Women who have experienced PE may also face additional health problems in later life, as the condition is associated with an increased risk of death from future cardiovascular disease, hypertension, stroke, renal impairment, metabolic syndrome, and diabetes. The life expectancy of women who developed preterm PE is reduced on average by 10 years. There is also significant impact on the infants in the long term, such as increased risks of insulin resistance, diabetes mellitus, coronary artery disease, and hypertension in infants born to pre‐eclamptic women. The International Federation of Gynecology and Obstetrics (FIGO) brought together international experts to discuss and evaluate current knowledge on PE and develop a document to frame the issues and suggest key actions to address the health burden posed by PE. FIGO's objectives, as outlined in this document, are: (1) To raise awareness of the links between PE and poor maternal and perinatal outcomes, as well as to the future health risks to mother and offspring, and demand a clearly defined global health agenda to tackle this issue; and (2) To create a consensus document that provides guidance for the first‐trimester screening and prevention of preterm PE, and to disseminate and encourage its use. Based on high‐quality evidence, the document outlines current global standards for the first‐trimester screening and prevention of preterm PE, which is in line with FIGO good clinical practice advice on first trimester screening and prevention of pre‐eclampsia in singleton pregnancy.1 It provides both the best and the most pragmatic recommendations according to the level of acceptability, feasibility, and ease of implementation that have the potential to produce the most significant impact in different resource settings. Suggestions are provided for a variety of different regional and resource settings based on their financial, human, and infrastructure resources, as well as for research priorities to bridge the current knowledge and evidence gap. To deal with the issue of PE, FIGO recommends the following: Public health focus: There should be greater international attention given to PE and to the links between maternal health and noncommunicable diseases (NCDs) on the Sustainable Developmental Goals agenda. Public health measures to increase awareness, access, affordability, and acceptance of preconception counselling, and prenatal and postnatal services for women of reproductive age should be prioritized. Greater efforts are required to raise awareness of the benefits of early prenatal visits targeted at reproductive‐aged women, particularly in low‐resource countries. Universal screening: All pregnant women should be screened for preterm PE during early pregnancy by the first‐trimester combined test with maternal risk factors and biomarkers as a one‐step procedure. The risk calculator is available free of charge at https://fetalmedicine.org/research/assess/preeclampsia. FIGO encourages all countries and its member associations to adopt and promote strategies to ensure this. The best combined test is one that includes maternal risk factors, measurements of mean arterial pressure (MAP), serum placental growth factor (PLGF), and uterine artery pulsatility index (UTPI). Where it is not possible to measure PLGF and/or UTPI, the baseline screening test should be a combination of maternal risk factors with MAP, and not maternal risk factors alone. If maternal serum pregnancy‐associated plasma protein A (PAPP‐A) is measured for routine first‐trimester screening for fetal aneuploidies, the result can be included for PE risk assessment. Variations to the full combined test would lead to a reduction in the performance screening. A woman is considered high risk when the risk is 1 in 100 or more based on the first‐trimester combined test with maternal risk factors, MAP, PLGF, and UTPI. Contingent screening: Where resources are limited, routine screening for preterm PE by maternal factors and MAP in all pregnancies and reserving measurements of PLGF and UTPI for a subgroup of the population (selected on the basis of the risk derived from screening by maternal factors and MAP) can be considered. Prophylactic measures: Following first‐trimester screening for preterm PE, women identified at high risk should receive aspirin prophylaxis commencing at 11–14+6 weeks of gestation at a dose of ~150 mg to be taken every night until 36 weeks of gestation, when delivery occurs, or when PE is diagnosed. Low‐dose aspirin should not be prescribed to all pregnant women. In women with low calcium intake (<800 mg/d), either calcium replacement (≤1 g elemental calcium/d) or calcium supplementation (1.5–2 g elemental calcium/d) may reduce the burden of both early‐ and late‐onset PE.

Impact of the contraceptive implant on maternal and neonatal morbidity and mortality in rural Papua New Guinea: a retrospective observational cohort study

OBJECTIVES

Using routinely collected birth data, this study sought to measure changes in maternal and neonatal morbidity and mortality after introduction of the levonorgestrel contraceptive implant into a large, rural island population in Papua New Guinea (PNG).

STUDY DESIGN

We conducted a retrospective observational study of birth records from 4251 births that occurred between January 2010 and December 2016 on Karkar Island, PNG. The primary outcome was the change in crude birth rate (CBR) before (2010-2012) and after (2014-2016) introduction of the implant. Secondary outcomes were the change in rates (per year/1000 births) of severe postpartum hemorrhage, postpartum infection, hospital readmission, prematurity (<37 weeks), low birth weight (<2500 g) and maternal and neonatal mortality. We also studied changes in the number of pregnancies affected by grand multiparity (≥4) and short interpregnancy interval (<12 months) for the same time periods. Data were analyzed using interrupted time series and Poisson regression.

RESULTS

CBR was stable until 2012 and then declined from 2014 (p<.0001). Following introduction of the implant, the annual rate/1000 births of selected adverse birth outcomes decreased between 56% and 74% (p<.0001). The number of women with parity ≥4 who gave birth decreased by 59% (p<.0001), and the number with interpregnancy interval <12 months decreased by 64% (p<.0001).

CONCLUSIONS

Introduction of the contraceptive implant was associated with reductions in CBR, maternal and neonatal morbidity, and the number of women with high-risk pregnancies giving birth.

IMPLICATIONS

These results encourage efforts to increase knowledge and availability of the contraceptive implant in low- and middle-income countries such as PNG. In cases where it reduces the CBR and the number of women with high-risk pregnancies birthing, the implant may have a beneficial impact on maternal and neonatal morbidity.

Developing evidence-based recommendations for optimal interpregnancy intervals in high-income countries: protocol for an international cohort study

INTRODUCTION

Short interpregnancy interval (IPI) has been linked to adverse pregnancy outcomes. WHO recommends waiting at least 2 years after a live birth and 6 months after miscarriage or induced termination before conception of another pregnancy. The evidence underpinning these recommendations largely relies on data from low/middle-income countries. Furthermore, recent epidemiological investigations have suggested that these studies may overestimate the effects of IPI due to residual confounding. Future investigations of IPI effects in high-income countries drawing from large, population-based data sources are needed to inform IPI recommendations. We aim to assess the impact of IPIs on maternal and child health outcomes in high-income countries.

METHODS AND ANALYSIS

This international longitudinal retrospective cohort study will include more than 18 million pregnancies, making it the largest study to investigate IPI in high-income countries. Population-based data from Australia, Finland, Norway and USA will be used. Birth records in each country will be used to identify consecutive pregnancies. Exact dates of birth and clinical best estimates of gestational length will be used to estimate IPI. Administrative birth and health data sources with >99% coverage in each country will be used to identify maternal sociodemographics, pregnancy complications, details of labour and delivery, birth and child health information. We will use matched and unmatched regression models to investigate the impact of IPI on maternal and infant outcomes, and conduct meta-analysis to pool results across countries.

ETHICS AND DISSEMINATION

Ethics boards at participating sites approved this research (approval was not required in Finland). Findings will be published in peer-reviewed journals and presented at international conferences, and will inform recommendations for optimal IPI in high-income countries. Findings will provide important information for women and families planning future pregnancies and for clinicians providing prenatal care and giving guidance on family planning.

Effects of interpregnancy interval on pregnancy complications: protocol for systematic review and meta-analysis

INTRODUCTION

Interpregnancy interval (IPI) is the length of time between a birth and conception of the next pregnancy. Evidence suggests that both short and long IPIs are at increased risk of adverse pregnancy and perinatal outcomes. Relatively less attention has been directed towards investigating the effect of IPI on pregnancy complications, and the studies that have been conducted have shown mixed results.This systematic review will aim to provide an update to the most recent available evidence on the effect of IPI on pregnancy complications.

METHOD AND ANALYSIS

We will search electronic databases such as Ovid/MEDLINE, EMBASE, CINAHL, Scopus, Web of Science and PubMed to identify peer-reviewed articles on the effects of IPI on pregnancy complications. We will include articles published from start of indexing until 12 February 2018 without any restriction to geographic setting. We will limit the search to literature published in English language and human subjects. Two independent reviewers will screen titles and abstracts and select full-text articles that meet the eligibility criteria. The Newcastle-Ottawa tool will be used to assess quality of observational studies. Where data permit, meta-analyses will be performed for individual pregnancy complications. A subgroup analyses by country categories (high-income vs low and middle-income countries) based on World Bank income group will be performed. Where meta-analysis is not possible, we will provide a description of data without further attempt to quantitatively pool results.

ETHICS AND DISSEMINATION

Formal ethical approval is not required as primary data will not be collected. The results will be published in peer-reviewed journals and presented at national and international conferences.

PROSPERO REGISTRATION NUMBER

CRD42018088578.

The Role of Extremes in Interpregnancy Interval in Women at Increased Risk for Adverse Obstetric Outcomes Due to Health Disparities: A Literature Review

Background:

The interpregnancy interval (IPI) defines the time between two consecutive gestations. In the general population, women with IPIs that fall outside the recommended 18-24 month range appear to be at modestly increased risk for adverse obstetric outcomes.

Objective:

The aim of this review was to assess the impact of extremes in IPI in populations with an increased baseline risk for adverse obstetric outcomes due to disparities in health and health care, including racial and ethnic groups, adolescents, and those of lower socioeconomic status.

Methods:

We conducted a MEDLINE/Pubmed literature search in February 2016. Identified articles were reviewed and assigned a level of evidence.

Results:

The 24 studies included in our final review were mainly retrospective with considerable heterogeneity in definitions and outcomes that prevented a quantitative meta-analysis.

Conclusion:

The results of our review suggest that at-risk populations may have an increased frequency of shortened IPIs though the impact appears to be moderate and inconsistent. There was insufficient evidence to draw meaningful conclusions regarding a prolonged IPI or the effect of interventions. Based on the current literature, under-served populations are more likely to have a shortened IPI which increased the incidence of prematurity and low birth weight in some groups though the effect on additional obstetric outcomes is difficult to assess

Interbirth Interval and Pregnancy Complications and Outcomes: Findings from the Pregnancy Risk Assessment Monitoring System

INTRODUCTION

Although the definition of a short interbirth interval has been inconsistent in the literature, Healthy People 2020 recommends that women wait at least 18 months after a live birth before attempting their next pregnancy. In the United States, approximately 33% of pregnancies are conceived within 18 months of a previous birth. Pregnancies that result from short interbirth intervals can pose serious risks. The objective of this study was to determine the association between interbirth interval and understudied pregnancy complications and outcomes, including small for gestational age (SGA) infants, premature rupture of membranes (PROM), preterm PROM (PPROM), placenta previa, and gestational diabetes, using Pregnancy Risk Assessment and Monitoring System data from Mississippi and Tennessee.

METHODS

This study collected self-reported information from 2212 women on interbirth interval (≤18 months, ie, short; 19-35 months, ie, intermediate; and ≥36 months, ie, long; referent), PPROM, placenta previa, and gestational diabetes. SGA and PROM data were obtained from birth certificates. Logistic regression was used to calculate odds ratios (ORs) and 95% CIs.

RESULTS

After adjustment, there were no strong associations between interbirth interval and PPROM, gestational diabetes, or SGA infants. However, women with shorter intervals had increased odds of PROM (short: OR, 3.54; 95% CI, 1.22-10.23 and intermediate: OR, 4.09; 95% CI, 1.28-13.03) and placenta previa (short: OR, 2.58; 95% CI, 1.10-6.05 and intermediate: OR, 1.69; 95% CI, 0.94-3.05).

DISCUSSION

The study's findings provide further support for encouraging women to space their pregnancies appropriately. Moreover, findings underscore the need to provide women with family planning services so that closely spaced pregnancies and unintended pregnancies can be avoided. Additional studies of the role of interbirth interval on these understudied pregnancy complications and outcomes are warranted.

Association between maternal interpregnancy interval after live birth or pregnancy termination and birth weight: a quantile regression analysis

We used quantile regression (QR) to assess if the length of the interpregnancy interval (IPI) after live birth and pregnancy termination is associated with weight in subsequent birth. The analysis included 9663 and 3400 women with IPI after live birth and pregnancy termination, respectively. For the women after live birth, an IPI < 12 months had negative effects at the 5th and 10th quantiles of the birth weight (BW) distribution. When the BW was beyond the 90th quantile, the BWs of newborns whose mothers with longer IPI (36-59 months) were higher than the reference group (18~23 months). For women after pregnancy termination in the 10^th quantile, it was observed that those pregnant women with IPIs between 36 and 47 months had a negative effect (150 g) on BW compared with the reference group. This finding revealed that mothers with IPI < 12 months resulted in a decrease of 85 g at 75th quantile. The impact of IPI > 119 months in the upper quantile (95^th) had an increase of 330 g in BW. Our results demonstrated that both short (<12 months) and long (>36 months) IPIs are independently associated with higher risks of low birth weight (LBW) and macrosomia.

Heterogeneous Effects of Birth Spacing on Neonatal Mortality Risks in Bangladesh

The negative relationship between birth interval length and neonatal mortality risks is well documented, but heterogeneity in this relationship has been largely ignored. Using the Bangladesh Maternal Mortality and Health Care Survey 2010, this study investigates how the effect of birth interval length on neonatal mortality risks varies by maternal age at birth and maternal education. There is significant variation in the effect of interval length on neonatal mortality along these dimensions. Young mothers and those with little education, both of which make up a large share of the Bangladeshi population, can disproportionately benefit from longer intervals. Because these results were obtained from within-family models, they are not due to unobservable heterogeneity between mothers. Targeting women with these characteristics may lead to significant improvements in neonatal mortality rates, but there are significant challenges in reaching them.

A first look at the effects of long inter-pregnancy interval and advanced maternal age on perinatal outcomes: A retrospective cohort study

BACKGROUND

After China's One-child Policy was replaced with the Two-child Policy in 2013, the rate of second pregnancies with a longer inter-pregnancy interval (IPI) has suddenly increased in that country; however, the effect of long IPIs (≥49 months) on perinatal outcomes remains unreported.

METHODS

This was a retrospective cohort study in China from July 2015 through June 2016. We used univariate and multivariate logistic regression models to test the associations among IPI, maternal age, and perinatal outcome (preterm delivery, term low birthweight, and small-for-gestational age). We included baseline factors and variables with biological plausibility as confounders.

RESULTS

Our analytic sample included 3309 second pregnancies. The mean IPI was 75.36 months. Compared with second pregnancies with a short IPI of 7-24 months, those with long IPIs had higher adjusted odds ratios (ORs) of preterm delivery (1.70-2.00 [95% CI 1.20-3.33]) and term low birthweight (2.16-2.68 [1.10-6.17]), but not small-for-gestational age. The mean maternal age at current delivery was 32.0 years. Compared with the reference group (25-29 years), second pregnancies for the oldest maternal age group (≥35 years) showed no statistically significant increased ORs for adverse perinatal outcomes.

CONCLUSION

Long IPI is a significant contributor to preterm delivery and term low birthweight. Health care providers need to pay close attention to preterm delivery prevention and fetal growth during prenatal care for second pregnancies where the mothers have long IPIs.

Interpregnancy Interval and Adverse Perinatal Outcomes: A Record-Linkage Study Using the Manitoba Population Research Data Repository

OBJECTIVE

To examine the association between the interpregnancy interval (IPI) and preterm birth, low birth weight, and SGA birth in a developed country with universal health coverage.

METHODS

We conducted a secondary analysis of data housed at the Manitoba Centre for Health Policy. All live births in Manitoba hospitals over a 29-year period were identified and consecutive births to the same mother were grouped into sibling pairs to calculate the IPI for the younger siblings. Logistic regression models were fit to examine the association between the IPI and adverse perinatal outcomes, adjusted for potentially confounding sociodemographic and clinical factors.

RESULTS

In a cohort of more than 171 000 births and relative to IPIs of 18 to 23 months, IPIs shorter than 12 and longer than 23 months were associated with significantly increased odds of preterm birth overall and both medically indicated and spontaneous preterm births, low birth weight, and SGA birth. The strongest association observed was for intervals shorter than 6 months and spontaneous preterm birth (adjusted OR 1.83, 95% CI 1.65-2.03). When the outcome was modelled as GA categories, the strongest association observed was for intervals shorter than 6 months and early preterm birth (<34 weeks' GA; adjusted OR 2.47, 95% CI 2.07-2.94).

CONCLUSION

If the associations observed between the IPI and adverse perinatal outcomes in this large, population-based cohort are causal, birth spacing could form an important target of public health messaging in Canada.

Inter-pregnancy interval and risk of recurrent pre-eclampsia: systematic review and meta-analysis

BACKGROUND

Women with a history of pre-eclampsia have a higher risk of developing pre-eclampsia in subsequent pregnancies. However, the role of the inter-pregnancy interval on this association is unclear.

OBJECTIVE

To explore the effect of inter-pregnancy interval on the risk of recurrent pre-eclampsia or eclampia.

SEARCH STRATEGY

MEDLINE, EMBASE and LILACS were searched (inception to July 2015).

SELECTION CRITERIA

Cohort studies assessing the risk of recurrent pre-eclampsia in the immediate subsequent pregnancy according to different birth intervals.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed screening, data extraction, methodological and quality assessment. Meta-analysis of adjusted odds ratios (aOR) with 95 % confidence intervals (CI) was used to measure the association between various interval lengths and recurrent pre-eclampsia or eclampsia.

MAIN RESULTS

We identified 1769 articles and finally included four studies with a total of 77,561 women. The meta-analysis of two studies showed that compared to inter-pregnancy intervals of 2-4 years, the aOR for recurrent pre-eclampsia was 1.01 [95 % CI 0.95 to 1.07, I(2) 0 %] with intervals of less than 2 years and 1.10 [95 % CI 1.02 to 1.19, I(2) 0 %] with intervals longer than 4 years.

CONCLUSION

Compared to inter-pregnancy intervals of 2 to 4 years, shorter intervals are not associated with an increased risk of recurrent pre-eclampsia but longer intervals appear to increase the risk. The results of this review should be interpreted with caution as included studies are observational and thus subject to possible confounding factors.

Interpregnancy interval and perinatal outcomes across Latin America from 1990 to 2009: a large multi-country study

OBJECTIVE

To determine the relationship of interpregnancy interval with maternal and offspring outcomes.

DESIGN

Retrospective study with data from the Perinatal Information System database of the Latin American Centre for Perinatology and Human Development, Uruguay.

SETTING

Latin America, 1990-2009.

POPULATION

A cohort of 894 476 women delivering singleton infants.

METHODS

During 1990-2009 the Perinatal Information System database of the Latin American Centre for Perinatology identified 894 476 women with defined interpregnancy intervals: i.e. the time elapsed between the date of the previous delivery and the first day of the last normal menstrual period for the index pregnancy. Using the interval 12-23 months as the reference category, multiple logistic regression estimated adjusted odds ratios (aORs) with 95% confidence intervals (95% CIs) of the association between various interval lengths and maternal and offspring outcomes.

MAIN OUTCOME MEASURES

Maternal death, pre-eclampsia, eclampsia, puerperal infection, fetal death, neonatal death, preterm birth, and low birthweight.

RESULTS

In the reference interval there was 0.05% maternal death, 1.00% postpartum haemorrhage, 2.80% pre-eclampsia, 0.15% eclampsia, 0.28% puerperal infection, 3.45% fetal death, 0.68% neonatal death, 12.33% preterm birth, and 9.73% low birthweight. Longer intervals had increased odds of pre-eclampsia (>72 months), fetal death (>108-119 months), and low birthweight (96-107 months). Short intervals of <12 months had increased odds of pre-eclampsia (aOR 0.80; 95% CI 0.76-0.85), neonatal death (aOR 1.18; 95% CI 1.08-1.28), and preterm birth (aOR 1.16; 95% CI 1.11-1.21). Statistically, the interval had no relationship with maternal death, eclampsia, and puerperal infection.

CONCLUSIONS

A short interpregnancy interval of <12 months is associated with pre-eclampsia, neonatal mortality, and preterm birth, but not with other maternal or offspring outcomes. Longer intervals of >72 months are associated with pre-eclampsia, fetal death, and low birthweight, but not with other maternal or offspring outcomes.

TWEETABLE ABSTRACT

A short interpregnancy interval of <12 months is associated with neonatal mortality and preterm birth.