A short interpregnancy interval is a risk factor for preterm birth and its recurrence

Contraceptive uptake in postpartum people with and without opioid use disorder and opioid use with co-occurring substance use

Background

Using contraception to delay pregnancy allows people with opioid use disorder (OUD) to choose when they are ready to continue their families. Yet, postpartum contraceptive uptake among people with OUD has not been well characterized.

Methods

Analyses used 73,811 pregnancy episodes among 61,221 people (2016-2021) from the St. Louis University-SSM Virtual Data Warehouse. OUD was defined from the year prior and through pregnancy. Contraceptive uptake was defined within 90-days after delivery. We used Generalized Estimating Equations-type multinomial logit models to assess association of OUD +/- co-occurring substance use disorders (SUDs) with any contraception (yes/no) and type of contraception (effective - pills, patch, ring, injection; or highly effective - long-acting reversible, LARC methods [intrauterine device, implant] and sterilization).

Results

The sample was 66.0 % white and average age was 27.7 years (±5.6). 32.5 % of pregnancies were followed by contraception initiation, 2.3 % had an OUD diagnosis, and 1.3 % OUD with co-occurring SUD. There was no association between OUD and postpartum contraception receipt, but OUD was associated with decreased highly effective compared to effective method initiation (aOR=0.76; 95 % CI: [0.64-0.91]). OUD plus co-occurring SUD was associated with decreased uptake across all contraception types (aOR=0.81[0.70-0.93]), specifically, highly-effective methods (aOR=0.48[0.38-0.61]).

Conclusions

Overall postpartum contraception uptake among people with OUD is comparable to uptake in the non-OUD population. People with OUD plus co-occurring SUDs are particularly unlikely to receive contraception. The reasons people choose contraceptive methods are complex and may differ by SUD severity. More information is needed to understand factors that impact postpartum contraception initiation.

Interpregnancy interval following missed abortion and the risk for preterm birth

OBJECTIVE

Short inter-pregnancy interval (IPI) of <18 months following a live birth, has been associated with adverse pregnancy outcome. This study aimed to evaluate whether a short IPI following a medically treated missed abortion (MA) poses similar perinatal risks in a subsequent pregnancy.

STUDY DESIGN

The retrospective analysis included patients with history of an MA at up to 10 weeks of gestation, treated with misoprostol (pgE1) only, and with a documented subsequent live pregnancy (2010-2022). 1110 Patients were allocated into two groups: IPI ≤18 months and IPI >18 months. The primary outcome was the risk for a spontaneous preterm birth (PTB) <37 weeks of gestation in the consecutive pregnancy. Secondary outcomes included maternal and neonatal adverse outcomes. Statistical analysis was performed using the Statistical Program for Social Sciences for Windows version 26 (SPSS Inc, Chicago, IL).

RESULTS

The cohort included 1,110 patients: 430 (38.74 %) patients with IPI <18 months and 680 (61.26 %) patients with IPI >18 months. The characteristics of the two groups were not significantly different. The rates of spontaneous PTB <37 and <34 weeks of gestation were significantly higher in the short vs. long IPI cohort (16.28 % vs. 7.06 % and 6.74 % vs. 5.0 %, respectively, p < 0.05). These patients also had a higher risk for Cesarean delivery (31.63 % vs. 23.34 %, p = 0.005) and postpartum hemorrhage (4.42 % vs. 2.06 %, p = 0.029) compared to patients with IPI >18 months. The observed differences remained statistically significant even after adjusting for potential confounding variables using multiple regression analysis. No other significant differences in neonatal or maternal outcomes were noted.

CONCLUSION

Short IPI (≤18 months) following a medical treatment MA may be associated with an increased risk of PTB, Cesarean delivery and PPH.

Association between interpregnancy interval and adverse perinatal outcomes among subsequent twin pregnancies: a nationwide population-based study

BACKGROUND

The existing evidence on the association between interpregnancy interval (IPI) and pregnancy outcomes primarily focuses on singleton pregnancies, with limited research on twin pregnancies.

OBJECTIVE

This study aimed to investigate the association between IPI and adverse perinatal outcomes in twin pregnancies.

STUDY DESIGN

This population-based, retrospective cohort study analyzed data from the National Center for Health Statistics in the United States between 2016 and 2020. We included multiparous women aged 18 to 45 years with live-born twins without congenital anomalies, born between 26 and 42 weeks of gestation. Poisson regression models, adjusted for potential confounders, were used to evaluate the associations between IPI and adverse outcomes, including preterm birth (PTB) <36 weeks, small for gestational age (SGA), neonatal intensive care unit (NICU) admission, neonatal composite morbidity, and infant death. Missing data on covariates were managed using multiple imputations. Dose-response analyses were performed using the restricted cubic splines (RCS) approach. Subgroup analyses were stratified by maternal age, parity, and combination of neonatal sex. Sensitivity analyses were conducted using complete data and excluding pregnancies with intervening events during the IPI.

RESULTS

A total of 143,014 twin pregnancies were included in the analysis. Compared to the referent group (IPI of 18-23 months), an IPI of less than 6 months was associated with an increased risk of PTB<36 weeks (RR, 1.21; 95% confidence interval [95% CI]: 1.17-1.25), SGA (RR, 1.11; 95% CI: 1.03-1.18), neonatal composite morbidity (RR, 1.19; 95% CI: 1.12-1.27), NICU admission (RR, 1.18; 95% CI: 1.14-1.22), and infant death (RR, 1.29; 95% CI: 1.05-1.60). An IPI of 5 years or more was associated with an increased risk of PTB<36 weeks (RR, 1.18; 95% CI: 1.15-1.21), SGA (RR, 1.24; 95% CI: 1.18-1.30), neonatal composite morbidity (RR, 1.10; 95% CI: 1.05-1.15), and NICU admission (RR, 1.14; 95% CI: 1.11-1.17). The dose-response analyses showed that these outcomes had U-shaped or J-shaped associations with IPI. The associations between IPI and the outcomes slightly differed by advanced maternal age, parity, and combination of neonatal sex. The sensitivity analyses yielded similar results to the main findings.

CONCLUSION

Extreme IPI, less than 6 months or more than 5 years, was associated with adverse outcomes in twin pregnancies. IPI could be used as a predictor for risk stratification in high-risk twin pregnancies.

Recurrent preterm delivery following twin versus singleton preterm delivery: A retrospective cohort

OBJECTIVE

The main risk factor for preterm delivery (PTD; <37 gestational weeks) is having a history of PTD. The aim of this research was to compare the risk for recurrent PTD following twin versus singleton gestation PTD.

METHODS

A retrospective population-based cohort study was performed, including all women who had two consecutive pregnancies, the first of which ended with PTD. The incidence of PTD recurrence was compared between women with PTD in twin versus singleton gestation. Multivariable logistic models were used to study the association between twinning status and PTD recurrence, and specifically by gestational age of the first PTD, inter-pregnancy interval (IPI), and mode of conception.

RESULTS

The study population included 15 590 women, of whom 1680 (10.8%) had twins in their index pregnancy and 13 910 (89.2%) had singletons. The incidence of recurrent PTD was 10.5% (n = 177) following twin PTD versus 21.9% (n = 3044) following singleton PTD (adjusted odds ratio = 0.50, 95% confidence interval 0.32-0.76, while controlling for confounding variables). The results were consistent while stratifying by IPI, gestational age of the first PTD, or mode of conception.

CONCLUSIONS

Women with PTD in twin gestations are at lower risk for recurrent PTD compared with women with singleton PTD.

Parental Perceptions of Counseling Regarding Interpregnancy Interval after Stillbirth or Neonatal Death

OBJECTIVE

Although guidelines exist regarding optimal interpregnancy interval (IPI) after live birth, both optimal IPI and counseling regarding recommended IPI (rIPI) after stillbirth or neonatal death is not well established. Our goal was to describe the counseling bereaved parents receive regarding IPI, parents' reactions to that counseling, and actual IPI after loss.

STUDY DESIGN

Bereaved parents who had a previous pregnancy result in stillbirth or neonatal death participated in a web-based survey. Questions included demographics, details of stillbirth or neonatal death, IPI counseling, and pregnancy after loss. Demographic information, rIPI, and ac'tual IPI were reported using descriptive statistics. The Wilcoxon's rank sum test was used to test the association between rIPI and mode of delivery. The Spearman's correlation was used to test the association between rIPI and maternal age.

RESULTS

A total of 275 surveys were analyzed. Mean gestational age of stillbirth delivery was 33.1 (standard deviation: 6.6) weeks. A total of 29% delivered via cesarean. Median rIPI was 6 (interquartile ratio [IQR]: 2-9) months, with the primary reason for IPI reported as the need to heal (74%). Delivery via cesarean was associated with longer rIPI, 9 versus 4.2 months (p < 0.0001). Maternal age was not associated with rIPI. Of 144 people who pursued pregnancy again, median time until attempting conception was 3.5 (IQR: 2-6) months. Median actual IPI was 6 (IQR: 4-10) months.

CONCLUSION

Bereaved parents receive a wide range of counseling regarding rIPI. The majority receive rIPI and pursue actual IPI shorter than current national and international recommendations for optimal IPI.

KEY POINTS

· There is variation in IPI recommendation after stillbirth/neonatal death.. · Cesarean birth is associated with longer IPI recommendation, but maternal age is not.. · Median IPI after stillbirth or neonatal death was short: 6 (IQR: 4-10) months..

Association of Medicaid Reimbursement Policies with Provision of Long-Acting Reversible Contraception in the Postpartum Period, 2012-2018

Background: To address reimbursement challenges associated with long-acting reversible contraception (LARC) in the postpartum period, state Medicaid programs have provided additional payments ("carve-outs"). Implementation has been heterogeneous, with states providing separate payments for the device only, procedure only, or both the device and procedure. Methods: Claims data were drawn from 210,994 deliveries in the United States between 2012 and 2018. Using generalized estimating equations, we assess the relationship between Medicaid carve-out policies and the likelihood of LARC placement at (1) 3 days postpartum, (2) 60 days postpartum, and (3) 1 year postpartum, in Medicaid and commercially insured populations. Results: Among Medicaid beneficiaries, the likelihood of receiving LARC was higher in states with any carve-out, compared with states without carve-outs, at 3 days (adjusted odds ratio [aOR] 1.49 [95% confidence interval: 1.33-1.67], p < 0.001), 60 days (aOR: 1.40 [95% CI: 1.35-1.46], p < 0.001), and 1 year postpartum (aOR: 1.15 [95% CI: 1.11-1.20], p < 0.001). Adjustments were made for geographic region, seasonality, and patient age. Heterogeneity was observed by carve-out type; device carve-outs were consistently associated with greater likelihood of postpartum LARC placement, compared with states with no carve-outs. Similar trends were observed among commercially insured patients. Conclusion: Findings support the effectiveness of Medicaid carve-outs on postpartum LARC provision, particularly for device carve-outs, which were associated with increased postpartum LARC placement at 3 days, 60 days, and 1 year postpartum. This outcome suggests that policies to address cost-related barriers associated with LARC devices may prove most useful in overcoming barriers to immediate postpartum LARC placement, with the overarching aim of promoting reproductive autonomy.

Association of interpregnancy interval with adverse pregnancy outcomes according to the outcomes of the preceding pregnancy: a longitudinal study with 4.7 million live births from Brazil

Background

Earlier studies have proposed a link between the Interpregnancy Interval (IPI) and unfavorable birth outcomes. However, it remains unclear if the outcomes of previous births could affect this relationship. We aimed to investigate whether the occurrence of adverse outcomes-small for gestational age (SGA), preterm birth (PTB), and low birth weight (LBW)-at the immediately preceding pregnancy could alter the association between IPI and the same outcomes at the subsequent pregnancy.

Methods

We used a population-based linked cohort from Brazil (2001-2015). IPI was measured as the difference, in months, between the preceding birth and subsequent conception. Outcomes included SGA (<10th birthweight percentile for gestational age and sex), LBW (<2500 g), and PTB (gestational age <37 weeks). We calculated risk ratios (RRs), using the IPI of 18-22 months as the reference IPI category, we also stratified by the number of adverse birth outcomes at the preceding pregnancy.

Findings

Among 4,788,279 births from 3,804,152 mothers, absolute risks for subsequent SGA, PTB, and LBW were higher for women with more adverse outcomes in the preceding delivery. The RR of SGA and LBW for IPIs <6 months were greater for women without previous adverse outcomes (SGA: 1.44 [95% Confidence Interval (CI): 1.41-1.46]; LBW: 1.49 [1.45-1.52]) compared to those with three previous adverse outcomes (SGA: 1.20 [1.10-1.29]; LBW: 1.24 [1.15-1.33]). IPIs ≥120 months were associated with greater increases in risk for LBW and PTB among women without previous birth outcomes (LBW: 1.59; [1.53-1.65]; PTB: 2.45 [2.39-2.52]) compared to women with three adverse outcomes at the index birth (LBW: 0.92 [0.78-1.06]; PTB: 1.66 [1.44-1.88]).

Interpretation

Our study suggests that women with prior adverse outcomes may have higher risks for adverse birth outcomes in subsequent pregnancies. However, risk changes due to differences in IPI length seem to have a lesser impact compared to women without a prior event. Considering maternal obstetric history is essential in birth spacing counseling.

Funding

Wellcome Trust225925/Z/22/Z.

Short Interpregnancy Intervals Among Women Experiencing Homelessness in Colorado

Importance

Short interpregnancy intervals (SIPIs) are associated with increased risk of adverse maternal and neonatal outcomes. Disparities exist across socioeconomic status, but there is little information on SIPIs among women experiencing homelessness.

Objective

To investigate (1) differences in rates and characteristics of SIPIs between women experiencing homelessness and domiciled women, (2) whether the association of homelessness with SIPIs differs across races and ethnicities, and (3) whether the association between SIPIs of less than 6 months (very short interpregnancy interval [VSIPIs]) and maternal and neonatal outcomes differs between participant groups.

Design, Setting, and Participants

This cohort study used a Colorado statewide database linking the Colorado All Payer Claims Database, Homeless Management Information System, death records, and infant birth records. Participants included all women who gave birth between January 1, 2016, and December 31, 2021. Data were analyzed from September 1, 2022, to May 10, 2023.

Exposures

Homelessness and race and ethnicity.

Main Outcomes and Measures

The primary outcome consisted of SIPI, a binary variable indicating whether the interval between delivery and conception of the subsequent pregnancy was shorter than 18 months. The association of VSIPI with maternal and neonatal outcomes was also tested.

Results

A total of 77 494 women (mean [SD] age, 30.7 [5.3] years) were included in the analyses, of whom 636 (0.8%) were women experiencing homelessness. The mean (SD) age was 29.5 (5.4) years for women experiencing homelessness and 30.7 (5.3) years for domiciled women. In terms of race and ethnicity, 39.3% were Hispanic, 7.3% were non-Hispanic Black, and 48.4% were non-Hispanic White. Associations between homelessness and higher odds of SIPI (adjusted odds ratio [AOR], 1.23 [95% CI, 1.04-1.46]) were found. Smaller associations between homelessness and SIPI were found among non-Hispanic Black (AOR, 0.59 [95% CI, 0.37-0.96]) and non-Hispanic White (AOR, 0.57 [95% CI, 0.39-0.84]) women compared with Hispanic women. A greater association of VSIPI with emergency department visits and low birth weight was found among women experiencing homelessness compared with domiciled women, although no significant differences were detected.

Conclusions and Relevance

In this cohort study of women who gave birth from 2016 to 2021, an association between homelessness and higher odds of SIPIs was found. These findings highlight the importance of conception management among women experiencing homelessness. Racial and ethnic disparities should be considered when designing interventions.

Social determinants among Black people during pregnancy following a short interpregnancy interval

BACKGROUND

Short interpregnancy interval has been shown to be a key contributor to infant mortality. Black pregnant people have a higher incidence of short interpregnancy interval than people of other races and ethnicities, as well as higher rates of infant mortality. Understanding the factors related to racial disparities in short interpregnancy interval and infant mortality are a public health priority.

OBJECTIVE

This study aimed to examine the relationship between social determinants of health and interpregnancy interval in Black pregnant people by comparing those with a short interpregnancy interval defined as <18 months with those with a referent interpregnancy interval defined as ≥18 months.

STUDY DESIGN

This was a nested case-control study from a prospective cohort analyzing social determinants of health in 576 postpartum patients at an urban medical center, 2011-2021. Sociodemographic, pregnancy, and maternal characteristic data were collected from participants' medical records. Structured interviews measured participants' health behaviors, physical environment, social support, health literacy, and structural drivers. Differences in social determinants of health among Black study participants were compared between those with a short interpregnancy interval (<18 months) and those with a referent interpregnancy interval (≥18 months). The odds ratios were calculated to assess the association between short interpregnancy interval and social determinants. Factors with significant differences between the short interpregnancy interval and referent interpregnancy interval groups in Black participants were compared with that of White groups for social context.

RESULTS

Black participants with a short interpregnancy interval were more likely to report financial support from the Special Supplemental Nutrition Program for Women, Infants, and Children (odds ratio, 2.4; 95% confidence interval, 1.2-5.1), negative feelings toward the pregnancy (odds ratio, 2.4; 95% confidence interval, 1.2-4.9), choosing not to breastfeed because they do not like it (odds ratio ,12.0; 95% confidence interval, 1.5-543.1), not receiving prenatal care as early as desired (odds ratio, 3.4; 95% confidence interval, 1.6-7.2) because of consid- eration of pregnancy termination (odds ratio, 5.2; 95% confidence interval, 1.2-30.5) and less likely to report low levels of social support (odds ratio, 0.3; 95% confidence interval, 0.1-0.8) than Black participants with a referent interpregnancy interval.

CONCLUSION

Social determinants of health that differed between participants with a short interpregnancy interval and those with a referent interpregnancy interval were Special Supplemental Nutrition Program for Women, Infants, and Children support, feelings toward the pregnancy, social support, breastfeeding intent, and delayed prenatal care because of consideration of abortion. Previous studies examining infant mortality risk factors used White people as the referent group when analyzing social determinants. Our study focused specifically on understanding the lives of Black pregnant people so that future public health initiatives focused on social determinants may attenuate the racial disparity of infant mortality in the United States.

Interpregnancy Interval After Stillbirth and Adverse Perinatal Outcomes

We used a retrospective cohort of 5,581 individuals to examine the association between interpregnancy interval (IPI) after stillbirth and pregnancy outcomes of preterm birth, preeclampsia, small for gestational age, recurrent stillbirth, infant death, and neonatal intensive care unit admission in the subsequent pregnancy. The IPI was divided in six categories, with 18-23 months as referent. Association between IPI category and adverse outcomes was determined with logistic regression models adjusted for maternal race and ethnicity, age, education, insurance, and gestational age at preceding stillbirth. Adverse perinatal outcome was common in pregnancies after stillbirth, with 26.7% of individuals delivering preterm. None of the IPI categories were associated with increased risk of adverse perinatal outcomes, including the shortest category (IPI less than 3 months). This finding is meaningful for bereaved parents who desire to conceive shortly after stillbirth.

Factors associated with short birth interval among reproductive-age women in East Africa

BACKGROUND

Child and maternal mortality continue as a major public health concern in East African countries. Optimal birth interval is a key strategy to curve the huge burden of maternal, neonatal, infant, and child mortality. To reduce the incidence of adverse pregnancy outcomes, the World Health Organization recommends a minimum of 33 months between two consecutive births. Even though short birth interval is most common in many East African countries, as to our search of literature there is limited study published on factors associated with short birth interval. Therefore, this study investigated factors associated with short birth intervals among women in East Africa.

OBJECTIVE

To identify factors associated with short birth intervals among reproductive-age women in East Africa based on the most recent demographic and health survey data.

DESIGN

A community-based cross-sectional study was conducted based on the most recent demographic and health survey data of 12 East African countries. A two-stage stratified cluster sampling technique was employed to recruit the study participants.

METHODS AND ANALYSIS

A total weighted sample of 105,782 reproductive-age women who had two or more births were included. A multilevel binary logistic regression model was fitted to identify factors associated with short birth interval. Four nested models were fitted and a model with the lowest deviance value (-2log-likelihood ratio) was chosen. In the multivariable multilevel binary logistic regression analysis, the adjusted odds ratio with the 95% confidence interval was reported to declare the statistical significance and strength of association between short birth interval and independent variables.

RESULTS

The prevalence of short birth interval in East Africa was 16.99% (95% confidence interval: 16.76%, 17.21%). Women aged 25-34 years, who completed their primary education, and did not perceive the distance to the health facility as a major problem had lower odds of short birth interval. On the contrary, women who belonged to the poorest household, made their own decisions with their husbands/partners or by their husbands or parents alone, lived in households headed by men, had unmet family planning needs, and were multiparous had higher odds of having short birth interval.

CONCLUSION

Nearly one-fifth of births in East Africa had short birth interval. Therefore, it is essential to promote family planning coverage, improve maternal education, and empower women to decrease the incidence of short birth intervals and their effects.

Optimizing postpartum contraception for high-risk obstetric patients

PURPOSE OF REVIEW

This review will focus on those who are at greatest risk of maternal and neonatal morbidity from a subsequent unplanned or short interval pregnancy and the interventions to increase contraceptive uptake in the postpartum period.

RECENT FINDINGS

Populations at highest risk of maternal or neonatal morbidity - those with a history of preterm birth or those with complex medical conditions - are also those at the highest risk for unintended pregnancies attributed to low-efficacy contraceptive failure/ noncontraceptive use, and many are discharged from birth hospitalization without understanding the importance of birth spacing related to their high-risk pregnancies. Current innovative strategies to improve postpartum contraception access and uptake among high-risk populations include utilizing the antenatal period to initiate contraception counseling, developing multidisciplinary teams, and incorporating multimedia-based educational tools. However, ongoing challenges that continue to pose barriers to contraception access include racial and economic disparities and the restructuring of obstetric care during the COVID-19 pandemic.

SUMMARY

Preventing an unintended short interval pregnancy by providing contraception in the postpartum period is one of the most modifiable risk factors for those at highest risk of subsequent maternal or neonatal morbidity and therefore should be prioritized by clinicians, hospitals, and insurance coverage.

Future Pregnancy Considerations after Premature Birth of an Infant Requiring Intensive Care: A Qualitative Study

BACKGROUND

Postpartum contraception counseling and method use vary widely among patients who had a preterm birth. We performed this study to explore what issues and concerns individuals with preterm infants requiring intensive care describe as influencing their postpartum contraceptive choices.

METHODS

We conducted a qualitative study using semi-structured interviews with participants who gave birth to a singleton preterm infant admitted to the neonatal intensive care unit (NICU). We explored pregnancy, childbirth, postpartum care, and NICU experiences, as well as future reproductive plans and postpartum contraceptive choices. Two coders used a constant-comparative approach to code transcripts and identify themes.

RESULTS

We interviewed 26 participants: 4 (15%) gave birth at less than 26, 6 (23%) at 26 to 27 6/7, 8 (31%) at 28 to 31 6/7, and 8 (31%) at 32 to 36 6/7 weeks of gestation. We identified three main themes related to future pregnancy plans and contraception choice. First, participants frequently described their preterm birth and their infants' NICU hospitalization as traumatic experiences that affected plans for future pregnancies. The loss of control in predicting or preventing a future preterm birth and uncertainty about their premature child's future medical needs resulted in participants wanting to avoid going through the same experience with another child. Second, participants chose contraception based on previous personal experiences, desired method features, and advice from others. Last, having a preterm birth did not result in any ambivalence among those who desired permanent contraception.

CONCLUSIONS

Preterm birth influences future pregnancy plans. When discussing reproductive goals with patients, clinicians should be aware of potential trauma associated with a premature birth, assess for whether patients want to discuss contraception, and center the conversation around individual needs if patients do desire contraceptive counseling.

A Scoping Review of Preterm Births in Sub-Saharan Africa: Burden, Risk Factors and Outcomes

Preterm births (PTB) are the leading cause of neonatal deaths, the majority of which occur in low- and middle-income countries, particularly those in Sub-Saharan Africa (SSA). Understanding the epidemiology of prematurity is an essential step towards tackling the challenge of PTB in the sub-continent. We performed a scoping review of the burden, predictors and outcomes of PTB in SSA. We searched PubMed, Embase, and three other databases for articles published from the database inception to 10 July 2021. Studies reporting the prevalence of PTB, the associated risk factors, and/or its outcomes were eligible for inclusion in this review. Our literature search identified 4441 publications, but only 181 met the inclusion criteria. Last menstrual period (LMP) was the most commonly used method of estimating gestational age. The prevalence of PTB in SSA ranged from 3.4% to 49.4%. Several risk factors of PTB were identified in this review. The most frequently reported risk factors (i.e., reported in ≥10 studies) were previous history of PTB, underutilization of antenatal care (<4 visits), premature rupture of membrane, maternal age (≤20 or ≥35 years), inter-pregnancy interval, malaria, HIV and hypertension in pregnancy. Premature babies had high rates of hospital admissions, were at risk of poor growth and development, and were also at a high risk of morbidity and mortality. There is a high burden of PTB in SSA. The true burden of PTB is underestimated due to the widespread use of LMP, an unreliable and often inaccurate method for estimating gestational age. The associated risk factors for PTB are mostly modifiable and require an all-inclusive intervention to reduce the burden and improve outcomes in SSA.

Patterns of recurrent preterm birth in Western Australia: A 36-year state-wide population-based study

BACKGROUND

It is known that a previous preterm birth increases the risk of a subsequent preterm birth, but a limited number of studies have examined this beyond two consecutive pregnancies.

AIMS

This study aimed to assess the risk and patterns of (recurrent) preterm birth up to the fourth pregnancy.

MATERIALS AND METHODS

We used Western Australian routinely linked population health datasets to identify women who had two or more consecutive singleton births (≥20 weeks gestation) from 1980 to 2015. A log-binomial model was used to calculate risk ratios (RRs) and 95% confidence interval (CIs) for preterm birth risk in the third and fourth deliveries by the combined outcomes of previous pregnancies.

RESULTS

We analysed 255 435 women with 651 726 births. About 7% of women had a preterm birth in the first delivery, and the rate of continuous preterm birth recurrence was 22.9% (second), 44.9% (third) and 58.5% (fourth) deliveries. The risk of preterm birth at the third delivery was highest for women with two prior indicated preterm births (RR 12.5, 95% CI: 11.3, 13.9) and for those whose first pregnancy was 32-36 weeks gestation, and second pregnancy was less than 32 weeks gestation (RR 11.8, 95% CI: 10.3, 13.5). There were similar findings for the second and fourth deliveries.

CONCLUSIONS

Our findings demonstrate that women with any prior preterm birth were at greater risk of preterm birth in subsequent pregnancies compared with women with only term births, and the risk increased with shorter gestational length, and the number of previous preterm deliveries, especially sequential ones.

Interpregnancy interval and prevalence of selected birth defects: A multistate study

BACKGROUND

Both short and long interpregnancy intervals (IPIs) have been associated with adverse birth outcomes. We undertook a multistate study to describe the prevalence of selected birth defects by IPI.

METHODS

We obtained data from nine population-based state birth defects registries for singleton live births in 2000-2009 among mothers with a previous live birth identified through birth certificates. IPI was calculated as the difference between prior birthdate and start of the current pregnancy (conception date). We estimated prevalence of selected defects per 10,000 live births and prevalence ratios (PRs) with 95% confidence intervals (CIs) overall and stratified by maternal age at previous birth and race/ethnicity. Primary analyses focused on short IPI < 6 months and long IPI ≥ 60 months compared to 18-23 months (referent). Sensitivity analyses limited to active-surveillance states and those with<10% missing IPI.

RESULTS

Among 5,147,962 eligible births, 6.3% had short IPI while 19.8% had long IPI. Compared to referent, prevalence with short IPI was elevated for gastroschisis (3.7, CI: 3.0-4.5 vs. 2.0, CI: 1.6-2.4) and with both short and long IPI for tetralogy of Fallot (short: 3.4, 2.8-4.2 long: 3.8, 3.4-4.3 vs. 2.7, 2.3-3.2) and cleft lip ± palate (short: 9.9, 8.8-11.2 long: 9.2, 8.5-9.8 vs. 8.4, 7.6-9.2). Stratified analyses identified additional associations, including elevated prevalence of anencephaly with short IPI in younger mothers and limb defects with long IPI in those ages 25-34 at prior birth. Sensitivity analyses showed similar results.

CONCLUSION

In this population-based study, we observed increased prevalence of several birth defects with short and long IPI.

Short and long interpregnancy interval and the risk for pediatric obstructive sleep apnea in the offspring

INTRODUCTION

Interpregnancy interval (IPI) is defined as the period between a live birth and the conception of a subsequent fetus. Both short (IPI < 6 months) and long IPI (IPI > 60 months) have been shown to increase the risk for adverse perinatal outcomes, some of which, are known risk factors for obstructive sleep apnea syndrome (OSAS) in the offspring.

AIMS

To study the association between IPI and risk for offspring OSAS, during a follow-up period of up to 18 years.

STUDY DESIGN

Population-based cohort.

SUBJECTS

In this population-based cohort analysis, all singleton live births, born to a mother with at least one previous birth occurring between 1991 and 2014, were included. Congenital malformations were excluded.

MATERIALS AND METHODS

Hospitalizations of the offspring due to OSAS diagnosis up to 18 years of age, were evaluated according to IPI length. Intermediate IPI (6-60 months) was considered as the reference. A Kaplan-Meier survival curve and a Cox hazards regression model were used to compare the incidence of OSAS between the groups, and to adjust for confounding variables.

RESULTS

The study population included 144,397 deliveries, of which 13.1% (n = 18,947) were followed by short IPI, 7.9% (n = 11,438) and 79.0% (n = 114,012) were followed by long and intermediate IPI, respectively. OSAS hospitalization rates were significantly higher among the long IPI group compared to intermediate and short IPIs (0.9%; 0.7% and 0.6%, respectively, p = .001). The association between long IPI and offspring pediatric OSAS remained significant after controlling for preterm delivery, maternal diabetes, and smoking, and mode of delivery, (adjusted HR = 1.45; 95% CI, 1.17-1.80).

CONCLUSIONS

Children born following long IPI are at increased risk for pediatric OSAS.

Determinants of short birth intervals among married women: a cross-sectional study in Karachi, Pakistan

INTRODUCTION

Birth spacing is a critical pathway to improving reproductive health. WHO recommends a minimum of 33-month interval between two consecutive births to reduce maternal, perinatal, infant morbidity and mortality. Our study evaluated factors associated with short birth intervals (SBIs) of less than 33 months between two consecutive births, in Karachi, Pakistan.

METHODS

We used data from a cross-sectional study among married women of reproductive age (MWRA) who had at least one live birth in the 6 years preceding the survey (N=2394). Information regarding their sociodemographic characteristics, reproductive history, fertility preferences, family planning history and a 6-year reproductive calendar were collected. To identify factors associated with SBIs, we fitted simple and multiple Cox proportional hazards models and computed HRs with their 95% CIs.

RESULTS

The median birth interval was 25 months (IQR: 14-39 months), with 22.9% (833) of births occurring within 33 months of the index birth. Women's increasing age (25-30 years (aHR 0.63 (0.53 to 0.75), 30+ years (aHR 0.29, 95% CI 0.22 to 0.39) compared with 20-24 years; secondary education (aHR 0.75, 95% CI 0.63 to 0.88), intermediate education (aHR 0.62, 95% CI 0.48 to 0.80), higher education (aHR 0.69, 95% CI 0.51 to 0.92) compared with no education, and a male child of the index birth (aHR 0.81, 95% CI 0.70 to 0.94) reduced the likelihood of SBIs. Women's younger age <20 years (aHR 1.24, 95% CI 1.05 to 1.24) compared with 20-24 years, and those who did not use contraception within 9 months of the index birth had a higher likelihood for SBIs for succeeding birth compared with those who used contraception (aHR 2.23, 95% CI 1.93 to 2.58).

CONCLUSION

Study shows that birth intervals in the study population are lower than the national average. To optimise birth intervals, programmes should target child spacing strategies and counsel MWRA on the benefits of optimal birth spacing, family planning services and contraceptive utilisation.

Can We Predict Preterm Delivery Based on the Previous Pregnancy?

(1) Background: Preterm deliveries (PTD, <37 gestational weeks) which occur in 5–18% of deliveries across the world, are associated with immediate and long-term offspring morbidity, as well as high costs to health systems. Our aim was to identify risk factors during the first pregnancy ending at term for PTD in the subsequent pregnancy. (2) Methods: A retrospective population- based nested case−control study was conducted, including all women with two first singleton consecutive deliveries. Women with PTD in the first pregnancy were excluded. Characteristics and complications of the first pregnancy were compared among cases, defined as women with PTD in their second pregnancy, and the controls, defined as women delivering at term in their second pregnancy. A multivariable logistic regression model was used to study the association between pregnancy complications (in the first pregnancy) and PTD (in the subsequent pregnancy), while adjusting for maternal age and the interpregnancy interval. (3) Results: A total of 39,780 women were included in the study, 5.2% (n = 2088) had PTD in their second pregnancy. Women with PTD, as compared to controls (i.e., delivered at term in second pregnancy), were more likely to have the following complications in their first pregnancy: perinatal mortality (0.4% vs. 1.0%), small for gestational age (12.4% vs. 8.1%), and preeclampsia (7.6% vs. 5.7%). In the multivariable model, after adjusting for maternal age, interpregnancy interval and co-morbidities, having any one of these first pregnancy complications was independently associated with an increased risk for PTD (adjusted OR = 1.44; 95%CI 1.28–1.62), and the risk was greater if two or more complications were diagnosed (adjusted OR = 2.09; 95%CI 1.47–3.00). These complications were also risk factors for early PTD (<34 gestational weeks), PTD with a systematic infectious disease in the background, and possibly with spontaneous PTD. (4) Conclusions: First pregnancy complications are associated with an increased risk for PTD in the subsequent pregnancy. First pregnancy, although ending at term, may serve as a window of opportunity to identify women at risk for future PTD.

Perinatal Loss: The Impact on Maternal Mental Health

Importance

Psychological reactions to perinatal loss, although often self-limited, may lead to significant psychological morbidities. Obstetrician-gynecologists and other maternal health providers play a key role in recognizing the range of psychological responses to perinatal loss and providing education, support, and treatment options to their patients.

Objective

This review aims to define psychological reactions associated with perinatal loss, examine psychotherapy and psychopharmacologic treatments for psychiatric morbidities, discuss interpregnancy interval following perinatal loss, and highlight brief, psychological interventions that can be implemented by maternal health providers.

Evidence Acquisition

Search terms "perinatal loss psychology," "reproductive loss grief," "perinatal psychopharmacology," "psychopharmacology grief," and "interpregnancy interval" were utilized to search PubMed, Google Scholar, and PsycINFO.

Results

Grief is an expected, normal response to perinatal loss. Psychological morbidities, including major depressive disorder, generalized anxiety disorder, and posttraumatic stress disorder, are also associated with perinatal loss. Risk factors for these conditions include history of a psychiatric illness, childlessness, unknown cause of perinatal loss, limited social support, and marital/relationship discord. Careful interviewing and brief screening measures can help identify patients who may suffer from depressive or anxiety disorders following reproductive loss. Patients with perinatal loss can benefit from psychological and possibly pharmacologic treatments. Recommended interpregnancy interval after perinatal loss should be customized by gestational age and cause of loss.

Conclusions and Relevance

Patients with perinatal loss emotionally benefit from their reproductive health care providers acknowledging the psychological aspects of reproductive loss, inquiring about their emotional needs, and providing information regarding grief and mental health referrals.

Fertility intentions and recent births among US abortion patients

OBJECTIVE

To examine fertility intentions among abortion patients and the potential of abortion for avoiding short birth intervals.

STUDY DESIGN

We used national data from a sample of more than 8000 individuals obtaining abortions in the United States in 2014. We created a measure of fertility intentions based on prior births and responses to an item asking about future childbearing expectations. We identify respondents who reported having a birth in the last 12 months as at risk of a short birth interval. We used simple logistic regression to assess for differences in these measures according to key demographic variables.

RESULTS

Most commonly, 39% of patients intended to have (more) children, with similar proportions wanting to delay a first birth (20%) or postpone a second or higher order birth (19%). Some 31% of abortion patients had completed childbearing; they had one or more prior births and did not want to have any more children. Similar proportions of respondents were not sure if they wanted to have children (16%) or did not want to have any children (15%). Among abortion patients who had children, 14% had had a birth in the prior year. We estimate that as many as 77,800 short birth intervals were averted in 2014 because individuals had access to abortion.

CONCLUSIONS

These findings support the view that abortion allows individuals to plan and space their births according to their reproductive life plans and intentions.

IMPLICATIONS

Access to abortion may help thousands of individuals in the United States avoid short birth intervals, potentially leading to improvements in maternal and child health.

Effects of short inter-pregnancy interval on maternal and perinatal outcomes: A cohort study of pregnant women in a low-income country

Background

Short inter-pregnancy interval (IPI) is a potential risk factor for adverse pregnancy outcomes. Previous reports from sub-Sahara Africa documented increasing incidence of short IPI but evidence is lacking in its effect on pregnancy outcome.

Aim

The study aimed to determine the effect of short IPI on pregnancy outcome in Nigeria.

Subjects and Methods

It was a prospective cohort study of 271 pregnant women receiving antenatal care in a tertiary hospital in Nigeria. For every eligible woman with short IPI (<18 months) recruited; a suitable control with IPI ≥18 months was selected. Statistical analysis was both inferential and descriptive using the statistical package for social sciences version 24 (SPSS Inc. Chicago, Illinois, USA) for windows. A P value of less than 0.05 was considered statistically significant.

Results

Incidence of maternal anemia was higher in women with short IPI than control (RR: 2.091; 95% CI: 1.4433.031; P < 0.001). Other maternal and perinatal outcome measures including premature rupture of membranes, preterm labor/delivery, pregnancy induced hypertension, third trimester bleeding, postpartum hemorrhage, and inadequate gestational weight gain did not show any significant association with short IPI (P > 0.05).

Conclusion

Short IPI is associated with anemia in pregnancy in Nigeria. Public health campaigns for improvement in uptake of family planning services and breastfeeding may help reduce the incidence of short IPI and anemia in low income countries.

Experiences with Prenatal and Postpartum Contraceptive Services among Women with a Preterm Birth

BACKGROUND

Providing postpartum contraception can help to achieve recommended interpregnancy intervals (≥18 months from birth to next pregnancy), decrease the risk of preterm birth, and thus improve maternal and infant health outcomes of future pregnancies. However, the experiences of women with preterm birth regarding contraceptive services have not been documented. We sought to better understand contraceptive counseling experiences and postpartum contraception of women with a preterm birth.

METHODS

We interviewed 35 women, ages 18-42 years, with a recent preterm birth in California. The transcribed interviews were analyzed using ATLAS.ti v.8.

RESULTS

Women had public (n = 15), private (n = 16), or no insurance (n = 4) at the time of the interview. Women were mainly Latina (n = 14), Caucasian (n = 9), or African American (n = 6); 15 women were foreign born. Women's experiences ranged from spontaneous preterm births to births with severe medical complications. We identified five themes that were associated with women's engagement in the contraceptive method choice and understanding of birth spacing: 1) timing and frequency of contraceptive counseling; 2) quality of patient-provider interaction and ability to follow up on questions; 3) women's personal experiences with contraceptive use and experiences of other women; 4) context in which contraceptive counseling was framed; and 5) system barriers to contraceptive use.

CONCLUSIONS

Postpartum contraceptive counseling should address women's preterm birth experience, medical conditions, age, contraceptive preference, and childbearing plans. Having a preterm birth intensifies gaps in hospital and outpatient clinic coordination and provider-patient communication that can lead to use of less effective or no contraceptive methods and risk of early subsequent unplanned pregnancies.

Short interpregnancy interval as a risk factor for preterm birth in non-Hispanic Black and White women in California

OBJECTIVE

Short interpregnancy interval (IPI) is associated with adverse pregnancy outcomes, including preterm birth (PTB < 37 weeks GA). We investigated whether short IPI (< 6 months) contributes to the higher PTB frequency among non-Hispanic Blacks (NHB).

STUDY DESIGN

Using a linked birth cohort > 1.5 million California live births, we examined frequencies of short IPI between racial/ethnic groups and estimated risks by multivariable logistic regression for spontaneous PTB. We expanded the study to births 1991-2012 and utilized a "within-mother" approach to permit methodologic inquiry about residual confounding.

RESULTS

NHB women had higher frequency (7.6%) of short IPI than non-Hispanic White (NHW) women (4.4%). Adjusted odds ratios for PTB and short IPI were 1.64 (95% CI 1.54, 1.76) for NHW and 1.49 (1.34, 1.65) for NHB. Using within-mother analysis did not produce substantially different results.

CONCLUSIONS

Short IPI is associated with PTB but does not explain risk disparity between NHWs and NHBs.

Interpregnancy interval and risk of stillbirth: a population-based case control study

PURPOSE

We examined the association between interpregnancy intervals (IPIs) and stillbirth (defined as fetal death ≥20 weeks), as both short and long IPIs have been associated with adverse perinatal outcomes. Prior pregnancy loss is also a known risk factor for stillbirth, and women who suffer a prior loss often have shorter IPIs. For these reasons, we also sought to quantify the proportion of the association between prior pregnancy loss and subsequent stillbirth risk that may be attributed to a short IPI.

METHODS

We used data from the Stillbirth Collaborative Research Network, a multisite case-control study conducted in 2006-2008, restricted to singleton pregnancies among multiparous or multigravid women (985 controls and 291 cases). We accounted for complex sample design and nonparticipation with weighted multivariable logistic regression.

RESULTS

In the adjusted models, IPIs <6 months, as compared with a reference of 18-23 months, were associated with increased odds of stillbirth (aOR 1.6, 95% CI: 0.8, 3.4). Long IPIs (60-100 months) were also associated with an increased odds of stillbirth (aOR 2.4, 95% CI: 1.2, 4.5). After control for covariates, about one-fifth (21.2%) of the association of prior pregnancy loss (stillbirth, ectopic pregnancy, molar pregnancy, or spontaneous abortion) and stillbirth may be attributable to a short IPI.

CONCLUSIONS

Our results suggest that women who experience a prior pregnancy loss may benefit from additional counseling on adequate birth spacing to reduce subsequent stillbirth risk.

Comparison of Health, Development, Maternal Bonding, and Poverty Among Children Born After Denial of Abortion vs After Pregnancies Subsequent to an Abortion

IMPORTANCE

Evidence indicates that there are potential health, development, and maternal bonding consequences for children born from unwanted pregnancies.

OBJECTIVE

To examine the association of women receiving or being denied a wanted abortion with their children's health and well-being.

DESIGN, SETTING, AND PARTICIPANTS

A 5-year longitudinal observational study with a quasi-experimental design conducted between January 18, 2008, and January 25, 2016, examined women who received abortions just under the gestational age limit of 30 abortion facilities across the United States and women who were denied abortion just beyond the gestational age limit in these facilities. Analyses compared the children of 146 women who were denied an abortion (index children) with children born to 182 women who received an abortion and had a subsequent child within 5 years (subsequent children). Interview-to-interview retention averaged 94.5% (6895 of 7293) across the 11 semi-annual interviews.

EXPOSURES

Being born after denial of abortion vs after a new pregnancy subsequent to an abortion.

MAIN OUTCOMES AND MEASURES

Perinatal outcomes and child health, child development, maternal bonding, socioeconomics, and household structure.

RESULTS

This study included 328 women who had children during the study period (mean [SD] age at study recruitment, 23.7 [4.9] years). There were no differences by study group in consent to participate in the study, completion of first interview, or continuation in the study. Among the 328 children in the study (146 index children and 182 subsequent children), there were 163 girls and 165 boys. Perinatal and child health outcomes were not different between subsequent and index children, and there was no clear pattern of delayed child development. However, mixed-effects models adjusting for clustered recruitment and multiple observations per child revealed that poor maternal bonding was more common for index children compared with subsequent children (9% vs 3%; adjusted odds ratio, 5.14; 95% CI, 1.48-17.85). Index children lived in households with lower incomes relative to the federal poverty level than did subsequent children (101% vs 132% of federal poverty level; adjusted regression coefficient, -0.31; 95% CI, -0.52 to -0.10), and were more likely to live in households without enough money to pay for basic living expenses (72% vs 55%; adjusted odds ratio, 5.16; 95% CI, 2.34-11.40).

CONCLUSIONS AND RELEVANCE

These findings suggest that access to abortion enables women to choose to have children at a time when they have more financial and emotional resources to devote to their children.

Factors associated with pregnancy intention among women who have experienced a short birth interval: findings from the 2009 to 2011 Mississippi and 2009 Tennessee Pregnancy Risk Assessment Monitoring System

PURPOSE

One-third of all pregnancies in the United States are conceived within 18 months of a prior live birth. Preventing unintended pregnancies may help to decrease the prevalence of pregnancies with these short interpregnancy intervals. However, data on factors associated with pregnancy intention among women who have had short birth intervals are sparse. Pregnancy Risk Assessment Monitoring System data were used to further evaluate these associations.

METHODS

Because only Mississippi and Tennessee Pregnancy Risk Assessment Monitoring System include a survey question about birth interval length, this analysis was limited to women from those states who recently had a short birth interval (n = 384). Pregnancy intention and demographic, lifestyle, and reproductive data were obtained from surveys and birth certificates. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Nearly 76% of women with short birth intervals reported their pregnancy as unintended. Women who were non-Hispanic black or consumed alcohol during pregnancy had statistically significant increased odds of reporting the pregnancy with a short birth interval as being unintended (OR = 3.98; 95% CI: 1.73-9.16 and OR = 10.56; 95% CI: 1.80-61.83, respectively).

CONCLUSIONS

Although all women should be counseled on postpartum contraceptive use, findings suggest that important subpopulations of women may benefit from more targeted counseling during prenatal care visits and the immediate postpartum hospital stay regarding the importance of using contraception to not only better space pregnancies but also prevent unintended pregnancies.

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.

Pregnancy after periviable birth: making the case for innovative delivery of interpregnancy care

Objective: Women who have had a spontaneous periviable delivery are at high risk for recurrent preterm delivery. The objective of our study was to determine interpregnancy interval (IPI) after periviable birth as well as percentage of women taking 17 alpha hydroxyprogesteronecaproate (17OHP-C) after periviable birth. We then examined the association between adherence with a postpartum visit after a periviable birth and IPI as well as receipt of 17OHP-C. Materials and methods: We included all women with a periviable delivery (20-26-week gestation) due to spontaneous preterm birth at Magee Women's Hospital between 2009 and 2014, who had their subsequent delivery at our institution during or before May of 2016. Information on maternal, fetal, and neonatal outcomes was obtained from the Magee Obstetrical Medical and Infant (MOMI) database as well as chart abstraction. We calculated IPI, proportion of women who received 17OHP-C in their next pregnancy, and attendance rates with a postpartum visit. The relationship between attendance with a postpartum visit and IPI, and receipt of 17OHP-C was examined with a logistic regression. Results: During the study period, 361 women had a spontaneous periviable birth. A total of 60 women had a subsequent delivery at Magee Women's Hospital. Only 33/60 (52.5%) presented for a postpartum visit after their periviable delivery. The median IPI for the cohort was 12.5 months (interquartile range: 6.4, 17.5 months) and 21.0% (n = 13) had an IPI less than 6 months. Adherence with the postpartum visit was not associated with an IPI less than 6 months. A total of 18.33% (11 women) did not receive 17OHP-C in their subsequent pregnancy. Women who attended a postpartum visit were much more likely to receive 17OHP-C (p = .001). Conclusions: Many women with a history of a periviable birth do not optimize strategies to reduce their risk of recurrent preterm birth. While attendance with a postpartum visit was associated with greater receipt of 17OHP-C in the subsequent pregnancy, given the overall poor rate of attendance with the postpartum visit in this cohort, novel strategies to counsel women about interpregnancy health are needed.

Disparities in Postpartum Contraceptive Counseling and Provision Among Mothers of Preterm Infants

OBJECTIVE

Use of effective contraception could be one method to decrease recurrent preterm birth by increasing intervals between pregnancies. We assessed correlates of contraceptive counseling and uptake among women who delivered preterm.

MATERIALS AND METHODS

This is a retrospective cohort study of women who delivered live-born singletons or twins before 32 weeks' gestation. We assessed documented contraceptive counseling and method uptake by postpartum discharge, using inpatient medical records, and correlates of highly effective contraception uptake by the postpartum visit using outpatient records.

RESULTS

Of 594 eligible women, 44.6% (n = 265) had documented inpatient contraceptive counseling, but only 21.4% (n = 127) left the hospital using a World Health Organization (WHO) tier 1 or 2 method. Women who were younger, non-Hispanic black, multiparous, and delivered at earlier gestational ages were more likely to have inpatient counseling documented. Compared with women with private insurance, women with public insurance were more likely to have documented counseling (22.8% vs. 87.5%, p < 0.001; adjusted odds ratio [aOR] 9.55, 95% confidence interval [CI] 5.31-17.2) and to uptake a WHO tier 1 or 2 method as an inpatient (5.8% vs. 52.0%, p < 0.001; aOR 9.51, 95% CI 4.78-18.9). Of the 175 women with outpatient records available who attended a postpartum visit, only 54.9% (n = 96) adopted a WHO tier 1 or tier 2 method.

CONCLUSION

Although all women in this cohort were at risk of recurrent preterm birth, counseling about contraception after a preterm birth (<32 weeks) was not universal. Women with multiple risk factors for recurrent preterm birth, such as multiparity and public insurance, were more likely to have received documented contraceptive counseling and highly effective contraceptives.

The Impact of Computing Interpregnancy Intervals Without Accounting for Intervening Pregnancy Events

BACKGROUND

Short interpregnancy intervals (IPI) are associated with poor birth outcomes. Often, only livebirths are considered to estimate IPI. The objective of our work is to explore whether the associations between demographic, behavioural, and pregnancy variables and IPI change when events other than livebirth are included.

METHODS

We used data from the 2006-10 and 2011-13 period of the National Survey of Family Growth (NSFG). We defined IPI using the conception date of the index pregnancy and the event date of the previous one ending in (i) livebirth; (ii) stillbirth; (iii) miscarriage; (iv) abortion; or (v) any of these events. Risk ratios (RR) were estimated for short IPI (<18 months), and demographic, pregnancy, and behavioural variables using log-linear models.

RESULTS

When intervening events are included, the association between short IPI and its predictors vary by definition, especially for unintended versus intended pregnancies (only livebirth risk ratio [RR] 1.34, 95% confidence interval [CI] 1.2, 1.5) versus livebirth and miscarriage RR 1.14, 95% CI 1.0, 1.3) and women older than 30 vs. younger than 20 at resolution of the previous pregnancy (only livebirth RR 1.22, 95% CI 1.0, 1.5 versus livebirth and miscarriage RR 1.36, 95% CI 1.2, 1.6).

CONCLUSIONS

Including miscarriage as an intervening event in the calculation of IPI changes the association between several risk factors and short IPI. However, the association between short IPI and preterm birth does not vary when different IPI calculations are used.

Postpartum Contraception and Interpregnancy Intervals Among Adolescent Mothers Accessing Public Services in California

Objective To determine the association of age at index birth with postpartum contraceptive use and optimal interpregnancy interval (IPI, defined as delivery to next pregnancy >18 months), controlling for provider type and client demographics among adolescent mothers who have repeat pregnancies. Methods California's 2008 birth records were linked to California's Medi-Cal and Family PACT claims data to identify 26,393 women with repeat births between 2002 and 2008, whose index birth occurred as an adolescent, and who received publicly-funded services within 18 months after the index birth. Multivariable regression analyses were conducted to examine the relationship between timing of contraception provision and interpregnancy intervals, adjusting for socio-demographic factors. Results Seventy-eight percent of adolescent women did not receive contraception at their first postpartum visit, and twenty-eight percent of adolescent women never received contraception from a Family PACT or Medi-Cal provider. Adolescents who were older at their index birth had lower rates of optimal IPIs. Native American, Asian-Pacific Islander and Latina women had lower rates of optimal IPIs compared to white women. Compared to those using only barrier methods, adolescent women receiving highly effective contraceptive methods had a 4.25 times higher odds of having an optimal IPI than those receiving hormonal methods (OR 2.10), or using no method (OR 0.70). Conclusion Effective postpartum contraceptive use and being a Family PACT provider were associated with optimal birth spacing among adolescent mothers, yet racial and ethnic disparities persisted. A missed opportunity was the provision of contraception at the first postpartum visit. Providers should aim to remove barriers to initiation of contraception at this visit.

A genome-wide association study identifies only two ancestry specific variants associated with spontaneous preterm birth

Preterm birth (PTB), or the delivery prior to 37 weeks of gestation, is a significant cause of infant morbidity and mortality. Although twin studies estimate that maternal genetic contributions account for approximately 30% of the incidence of PTB, and other studies reported fetal gene polymorphism association, to date no consistent associations have been identified. In this study, we performed the largest reported genome-wide association study analysis on 1,349 cases of PTB and 12,595 ancestry-matched controls from the focusing on genomic fetal signals. We tested over 2 million single nucleotide polymorphisms (SNPs) for associations with PTB across five subpopulations: African (AFR), the Americas (AMR), European, South Asian, and East Asian. We identified only two intergenic loci associated with PTB at a genome-wide level of significance: rs17591250 (P = 4.55E-09) on chromosome 1 in the AFR population and rs1979081 (P = 3.72E-08) on chromosome 8 in the AMR group. We have queried several existing replication cohorts and found no support of these associations. We conclude that the fetal genetic contribution to PTB is unlikely due to single common genetic variant, but could be explained by interactions of multiple common variants, or of rare variants affected by environmental influences, all not detectable using a GWAS alone.

Racial and ethnic differences in preterm birth: A complex, multifactorial problem

Preterm birth remains the leading cause of morbidity and mortality among nonanomalous neonates, and is a major public health problem. Non-Hispanic black women have a 2-fold greater risk for preterm birth compared with non-Hispanic white race. The reasons for this disparity are poorly understood and cannot be explained solely by sociodemographic factors. Underlying factors including a complex interaction between maternal, paternal, and fetal genetics, epigenetics, the microbiome, and these sociodemographic risk factors likely underlies the differences between racial groups, but these relationships are currently poorly understood. This article reviews the epidemiology of disparities in preterm birth rates and adverse pregnancy outcomes and discuss possible explanations for the racial and ethnic differences, while examining potential solutions to this major public health problem.

Pathophysiology of preterm labor with intact membranes

Preterm labor with intact membranes is a major cause of spontaneous preterm birth (sPTB). To prevent sPTB a clear understanding is needed of the hormonal interactions that initiate labor. The steroid hormone progesterone acting via its nuclear progesterone receptors (PRs) in uterine cells is essential for the establishment and maintenance of pregnancy and disruption of PR signaling (i.e., functional progesterone/PR withdrawal) is key trigger for labor. The process of parturition is also associated with inflammation within the uterine tissues and it is now generally accepted that inflammatory stimuli from multiple extrinsic and intrinsic sources induce labor. Recent studies suggest inflammatory stimuli induce labor by affecting PR transcriptional activity in uterine cells to cause functional progesterone/PR withdrawal. Advances in understanding the functional interaction of inflammatory load on the pregnancy uterus and progesterone/PR signaling is opening novel areas of research and may lead to rational therapeutic strategies to effectively prevent sPTB.

Age at reproductive debut: Developmental predictors and consequences for lactation, infant mass, and subsequent reproduction in rhesus macaques (Macaca mulatta)

OBJECTIVES

The age at which females initiate their reproductive career is a critical life-history parameter with potential consequences on their residual reproductive value and lifetime fitness. The age at reproductive debut may be intimately tied to the somatic capacity of the mother to rear her young, but relatively little is known about the influence of age of first birth on milk synthesis within a broader framework of reproductive scheduling, infant outcomes, and other life-history tradeoffs.

MATERIAL AND METHODS

Our study investigated the predictors of age at first reproduction among 108 captive rhesus macaque (Macaca mulatta) females, and associations with their milk synthesis at peak lactation, infant mass, and ability to subsequently conceive and reproduce.

RESULTS

The majority of females reproduced in their fourth year (typical breeders); far fewer initiated their reproductive career one year earlier or one year later (respectively early and late breeders). Early breeders (3-year-old) benefited from highly favorable early life development (better juvenile growth, high dominance rank) to accelerate reproduction, but were impaired in milk synthesis due to lower somatic resources and their own continued growth. Comparatively, late breeders suffered from poor developmental conditions, only partially compensated by their delayed reproduction, and evinced compromised milk synthesis. Typical breeders not only produced higher available milk energy but also had best reproductive performance during the breeding and birth seasons following primiparity.

DISCUSSION

Here, we refine and extend our understanding of how life-history tradeoffs manifest in the magnitude, sources, and consequences of variation in age of reproductive debut. These findings provide insight into primate reproductive flexibility in the context of constraints and opportunities.

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.

Short interpregnancy interval increases the risk of preterm premature rupture of membranes and early delivery

OBJECTIVES

Preterm premature rupture of membranes (PPROM) is a major contributor to overall preterm birth (PTB) rates. A short interpregnancy interval (IPI) is a well-known risk factor for PTB. It is unknown if a short IPI specifically affects the risk of developing PPROM in a subsequent pregnancy. We sought to determine the association between IPI and the risk of PPROM in a subsequent pregnancy.

METHODS

A retrospective cohort study using the Missouri birth certificate database of singleton births from 2003 to 2013 was conducted. A short IPI (delivery of the prior pregnancy to conception of the index pregnancy) was defined as ≤6 months. IPI >6 months was categorized into two groups: IPI 7-23 months and IPI ≥24 months. PPROM was defined as premature rupture of membranes between 16⁰ and 36⁶ weeks. Multivariable logistic regression was conducted to determine the association between IPI and PPROM while controlling for maternal age, race, body mass index (BMI), education level, use of social services (Medicaid insurance, food stamps, or participation in the WIC [Women, Infants, and Children] program), tobacco use, and history of PTB. Secondary outcome included the gestational age at delivery, categorized into five subgroups (≤24⁰, 24¹-28⁰, 28¹-32⁰, 32¹-34⁰, and 34¹-36⁶ weeks).

RESULTS

474,957 subjects with singleton gestations had data available to calculate the IPI. Of these, 1.4% (n = 6797) experienced PPROM. IPI ≤6 months was significantly associated with an increased risk of developing PPROM compared with patients with IPI ≥24 months (odds ratio (OR) 1.80, 95% CI 1.70-1.90, p < .001). A higher proportion of women with IPI ≤6 months delivered between 28¹ and 32⁰ weeks compared to the other two IPI groups (27.0 versus 15.0 and 16.4%, p < .001). Individual maternal factors associated with an increased risk of PPROM included advanced maternal age, African American race, BMI <18.5 kg/m², BMI ≥30 kg/m², use of social services, tobacco use, and a prior PTB.

CONCLUSION

Our data demonstrate that an IPI of ≤6 months is significantly associated with an increased risk of developing PPROM in the subsequent pregnancy. Of greater clinical relevance is that these women were more likely to deliver between 28¹ and 32⁰ weeks as compared with women with a longer IPI. Novel to this study is the establishment of a specific link between a short IPI and PPROM with subsequent early delivery. Several maternal demographic factors known to be associated with PTB risk were also found to be associated with an increased risk of PPROM. Further studies are necessary to elucidate plausible biologic mechanisms ultimately leading to the development and implementation of preventive and therapeutic strategies for this high-risk cohort.

Short interpregnancy intervals and associated risk of preterm birth in Asians and Pacific Islanders

PURPOSE

The prevalence of short interpregnancy intervals (IPIs) and associated rates of preterm birth has been understudied in Asian and Pacific Islander populations. We sought to estimate rates of short IPI among Asian subgroups and Pacific Islanders and associated risk of preterm birth.

MATERIALS AND METHODS

For this retrospective cohort study, we linked records of women in California with a first birth in 1999-2000 and a second birth before 2005 with hospital discharge data. We used multivariate modeling to determine whether specific Asian ethnicities and Pacific Islanders were at greater risk of short IPI (<6 months, 6-18 months) and if a short IPI increased risk for preterm birth in these groups.

RESULTS

Our sample included 189,931 women. In multivariable analyses, Asian subgroups and Pacific Islanders were more likely to have an IPI <6 months than were White women (Pacific Islanders: OR 3.31 (95%CI [2.7, 4.1]); Filipinas: OR 1.51 (95%CI [1.33, 1.71]); Southeast Asians: OR 1.93 (95%CI [1.73, 2.1]); East Asians: OR 1.65 (95%CI [1.48, 1.84]); other Asians: OR 2.04 (95%CI [1.70, 2.4])).

CONCLUSIONS

Asian and Pacific Islander women have higher rates of IPI <6 months, but this did not significantly increase their risk of preterm birth.

Preterm Birth: Analysis of Longitudinal Data on Siblings Based on Random-Effects Logit Models

INTRODUCTION

The literature about the determinants of a preterm birth is still controversial. We approach the analysis of these determinants distinguishing between woman's observable characteristics, which may change over time, and unobservable woman's characteristics, which are time invariant and explain the dependence between the typology (normal or preterm) of consecutive births.

METHODS

We rely on a longitudinal dataset about 28,603 women who delivered for the first time in the period 2005-2013 in the Umbria Region (Italy). We consider singleton physiological pregnancies originating from natural conceptions with birthweight of at least 500 g and gestational age between 24 and 42 weeks; the overall number of deliveries is 34,224. The dataset is based on the Standard Certificates of Life Birth collected in the region in the same period. We estimate two types of logit model for the event that the birth is preterm. The first model is pooled and accounts for the information about possible previous preterm deliveries, including the lagged response among the covariates. The second model takes explicitly into account the longitudinal structure of data through the introduction of a random effect that summarizes all the (time invariant) unobservable characteristics of a woman affecting the probability of a preterm birth.

RESULTS

The estimated models provide evidence that the probability of a preterm birth depends on certain woman's demographic and socioeconomic characteristics, other than on the previous history in terms of miscarriages and the baby's gender. Besides, as the random-effects model fits significantly better than the pooled model with lagged response, we conclude for a spurious state dependence between repeated preterm deliveries.

CONCLUSION

The proposed analysis represents a useful tool to detect profiles of women with a high risk of preterm delivery. Such profiles are detected taking into account observable woman's demographic and socioeconomic characteristics as well as unobservable and time-constant characteristics, possibly related to the woman's genetic makeup.

TRIAL REGISTRATION

Not applicable.

Georgia's Medicaid Family Planning Waiver: Working Together with Title X to Enhance Access to and Use of Contraceptive and Preventive Health Services

PURPOSE

We sought to assess the impact of Georgia's family planning demonstration waiver upon access to and use of contraceptive and preventive health services within Title X and Medicaid.

PROCEDURES

Georgia Title X and Medicaid data for January 2009 through December 2013 (before and after the waiver), restricting Title X data to women targeted by the waiver (18-44 years, incomes from 25% and 50% through 200% of the federal poverty level [FPL]) was assembled by quarter and marginal effects of the changes before and after waiver implementation were derived using multivariate regression models.

FINDINGS

After implementation, there was a significant increase in the probability of Title X clients in the waiver-targeted age and income ranges who had Medicaid versus no insurance and who exited the encounter with higher effectiveness contraceptive methods, including long-acting reversible contraceptives (LARCs), and with cervical cytology and sexually transmitted infection testing. In the Medicaid data from 2009 to 2013, there was an increase in the mean number of encounters per enrollee (2.19 vs. 2.42) and in LARC users; however, the percentage of all Georgia women living under 200% of the FPL with a family planning encounter in Title X and Medicaid decreased from 19% to 15%.

CONCLUSIONS

Our findings suggest that implementation of the Georgia family planning demonstration waiver contributed to the increased use of higher effectiveness contraceptive methods, including LARCs, within the Medicaid and Title X programs as well as the increased use of preventive screenings among Title X clients. However, when the full population of low-income Georgia women targeted by the waiver was considered, a greater percentage was not served over the demonstration period.

Interpregnancy interval after live birth or pregnancy termination and estimated risk of preterm birth: a retrospective cohort study

OBJECTIVES

We assessed whether interpregnancy interval (IPI) length after live birth and after pregnancy termination was associated with preterm birth (PTB).

DESIGN

Multiyear birth cohort.

SETTINGS

Fetal death, birth and infant death certificates in California merged with Office of Statewide Health Planning and Development.

POPULATION

One million California live births (2007-10) after live birth and after pregnancy termination.

METHODS

Logistic regression was used to estimate odds ratios (ORs) of PTB of 20-36 weeks of gestation and its subcategories for IPIs after a live birth and after a pregnancy termination. We used conditional logistic regression (two IPIs/mother) to investigate associations within mothers.

MAIN OUTCOME MEASURE

PTB relative to gestations of ≥ 37 weeks.

RESULTS

Analyses included 971 211 women with IPI after live birth, and 138 405 women with IPI after pregnancy termination with 30.6% and 74.6% having intervals of <18 months, respectively. IPIs of <6 months or 6-11 months after live birth showed increased odds of PTB adjusted ORs for PTB of 1.71 (95% CI 1.65-1.78) and 1.20 (95% CI 1.16-1.24), respectively compared with intervals of 18-23 months. An IPI >36 months (versus 18-23 months) was associated with increased odds for PTB. Short IPI after pregnancy termination showed a decreased OR of 0.87 (95% CI 0.81-0.94). The within-mother analysis showed the association of increased odds of PTB for short IPI, but not for long IPI.

CONCLUSIONS

Women with IPI <1 or >3 years after a live birth were at increased odds of PTB-an important group for intervention to reduce PTB. Short IPI after pregnancy termination was associated with reduced odds for PTB and needs to be further explored.

TWEETABLE ABSTRACT

Short and long IPI after live birth, but not after pregnancy termination, showed increased odds for PTB.

The effect of maternity care coordination services on utilization of postpartum contraceptive services

OBJECTIVE

To examine whether maternity care coordination (MCC) services are associated with utilization of postpartum contraceptive services.

METHODS

Using a random sample of 7120 live births, we analyzed administrative data to assess whether MCC services affected utilization of contraceptive services within 3months of delivery. Treatment groups were constructed as MCC during the prenatal period only (n=531), MCC in both the prenatal and postpartum periods (n=1723) and a non-MCC control group (n=4866). Inverse probability of treatment weights (IPTWs) were calculated and applied to balance baseline risk factors across groups. We used the IPTW linear probability model to estimate postpartum contraceptive service utilization, controlling for demographic, social, reproductive and medical home enrollment characteristics.

RESULTS

At 3months postpartum, MCC participation was associated with a 19-percentage point higher level of utilization of postpartum contraceptive services among women who received both prenatal and postpartum care coordination services (p<.001), as compared with controls. Women who received only prenatal MCC services showed no difference in utilization of services at 3months postpartum from non-MCC controls. Sensitivity modeling showed the effect of MCC was independent of postpartum obstetrical care. Additionally, MCC had differential treatment effects across subpopulations based on maternal age, race, ethnicity and education; women who were white and did not have a medical home were more likely to benefit from MCC services in initiating postpartum contraceptives.

CONCLUSIONS

MCC programs may be instrumental in increasing timely utilization of postpartum contraceptive services, but continuation of the intervention into the postpartum period is critical.

IMPLICATION

MCC offered both prenatally and in the postpartum period appears to complement clinical care by increasing postpartum contraceptive service utilization. Providers should consider the potential added benefits of care coordination services in tandem with traditional obstetric care to increase postpartum contraceptive use and subsequently reduce short birth intervals.

Postpartum contraception needs of women with preterm infants in the neonatal intensive care unit

OBJECTIVES

To evaluate postpartum contraception experiences of mothers with premature infants in the neonatal intensive care unit (NICU), their knowledge of risk factors for preterm delivery and their interest in a family planning clinic located near the NICU.

STUDY DESIGN

This is a cross-sectional survey of English or Spanish-speaking women 18 or older whose premature neonate had been in the NICU for 5 days or more in a current stable condition.

RESULTS

A total of 95 women were interviewed at a median of 2.7 weeks postpartum (range 0.6-12.9). Approximately 75% of women were currently using or planning to use contraception, with 33% using less effective methods. Half of women reported they would obtain contraception at a family planning clinic near the NICU. Only 32% identified a short interpregnancy interval as a risk factor for preterm delivery.

CONCLUSION

Lack of knowledge of short interpregnancy interval as a risk factor for a future preterm delivery highlights the need to address postpartum contraception education and provision in this high-risk population.

Postpartum contraceptive use among women with a recent preterm birth

OBJECTIVE

The objective of the study was to evaluate the associations between postpartum contraception and having a recent preterm birth.

STUDY DESIGN

Population-based data from the Pregnancy Risk Assessment Monitoring System in 9 states were used to estimate the postpartum use of highly or moderately effective contraception (sterilization, intrauterine device, implants, shots, pills, patch, and ring) and user-independent contraception (sterilization, implants, and intrauterine device) among women with recent live births (2009-2011). We assessed the differences in contraception by gestational age (≤27, 28-33, or 34-36 weeks vs term [≥37 weeks]) and modeled the associations using multivariable logistic regression with weighted data.

RESULTS

A higher percentage of women with recent extreme preterm birth (≤27 weeks) reported using no postpartum method (31%) compared with all other women (15-16%). Women delivering extreme preterm infants had a decreased odds of using highly or moderately effective methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.6) and user-independent methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.7) compared with women having term births. Wanting to get pregnant was more frequently reported as a reason for contraceptive nonuse by women with an extreme preterm birth overall (45%) compared with all other women (15-18%, P < .0001). Infant death occurred in 41% of extreme preterm births and more than half of these mothers (54%) reported wanting to become pregnant as the reason for contraceptive nonuse.

CONCLUSION

During contraceptive counseling with women who had recent preterm births, providers should address an optimal pregnancy interval and consider that women with recent extreme preterm birth, particularly those whose infants died, may not use contraception because they want to get pregnant.

Risk factors associated with preterm birth after a prior term delivery

OBJECTIVE

The objective of this study was to assess the presence of newly acquired preterm birth (PTB) risk factors among primiparous women with no prior history of PTB.

DESIGN

Case-control study.

SETTING

Deliveries occurring within a large healthcare system from 2002 to 2012.

POPULATION

Women with their first two consecutive pregnancies carried to ≥20(0/7)  weeks' gestation.

METHODS

Those delivering the first pregnancy at term and the second preterm ≥20(0/7) and <37(0/7)  weeks (term-preterm cases) were compared with women with a term birth in their first two pregnancies (term-term controls). Social factors with the potential to change between the first and second pregnancies and intrapartum labour characteristics in the first pregnancy were compared between cases and controls.

MAIN OUTCOME MEASURES

Risk factors for term-preterm sequence.

RESULTS

About 38 215 women met inclusion criteria; 1353 (3.8%) were term-preterm cases. Cases and controls were similar with regard to race/ethnicity and maternal age at the time of the first and second deliveries. Cases delivered their second pregnancy approximately 3 weeks earlier (35.7 versus 39.1, P < 0.001). In multivariable models accounting for known PTB risk factors, women with a caesarean delivery in the first pregnancy [adjusted odds ratio (aOR) = 2.20; 95% confidence interval (CI) 1.57-3.08], new tobacco use (aOR = 2.33; 95% CI 1.61-3.38), and an interpregnancy interval <18 months (aOR = 1.37; 95% CI 1.21-1.55) were at increased risk of term-preterm sequence.

CONCLUSION

Caesarean delivery in the first pregnancy, new tobacco use, and short interpregnancy interval <18 months are significant risk factors for term-preterm sequence. Women should receive postpartum counselling regarding appropriate interpregnancy interval and cessation of tobacco use.

TWEETABLE ABSTRACT

Caesarean delivery in the 1st pregnancy is a significant risk factor for preterm birth following a term delivery.

Incidence and risk factors for recurrent spontaneous preterm birth: A retrospective cohort study in Japan

AIM

The aim of this study was to assess the incidence and risk factors for recurrent spontaneous preterm birth (PTB) in Japan.

MATERIAL AND METHODS

A retrospective cohort study was conducted at five tertiary perinatal centers in Osaka, Japan from 2008 through 2012. Perinatal data were collected from medical records of women with a singleton gestation and a previous spontaneous PTB. Exclusion criteria were first-trimester spontaneous abortion, first antenatal visit beyond 14 weeks of gestation, and previous PTB with medical indications, placenta previa, abruptio placenta, multiple pregnancy, fetal anomaly, and antepartum fetal demise. The associations between recurrent spontaneous PTB and perinatal factors were evaluated by logistic regression analysis.

RESULTS

Of 547 women with a previous spontaneous PTB, 89 (16.3%) suffered a recurrent spontaneous PTB. The risk factors for recurrence included multiple previous spontaneous PTB (adjusted odds ratio [aOR]: 2.26; 95% confidence interval [CI]: 1.19-4.30; P = 0.013), no previous term birth (aOR: 2.08; 95%CI: 1.24-3.49; P = 0.005), and interpregnancy interval < 12 months (aOR: 2.13; 95%CI: 1.17-3.85; P = 0.013).

CONCLUSION

Approximately one in six women with a previous spontaneous PTB suffered a recurrent spontaneous PTB. Multiple previous spontaneous PTB, no previous term birth, and short interpregnancy interval were independent risk factors for recurrence.