Prenatal care and subsequent birth intervals

Comparing approaches to identify live births using the Transformed Medicaid Statistical Information System

OBJECTIVE

To evaluate the performance of different approaches for identifying live births using Transformed Medicaid Statistical Information System Analytic Files (TAF).

DATA SOURCES

The primary data source for this study were TAF inpatient (IP), other services (OT), and demographic and eligibility files. These data contain administrative claims for Medicaid enrollees in all 50 states and the District of Columbia from January 1, 2018 to December 31, 2018.

STUDY DESIGN

We compared five approaches for identifying live birth counts obtained from the TAF IP and OT data with the Centers for Disease Control and Prevention (CDC) Natality data-the gold standard for birth counts at the state level.

DATA COLLECTION/EXTRACTION METHODS

The five approaches used varying combinations of diagnosis and procedure, revenue, and place of service codes to identify live births. Approaches 1 and 2 follow guidance developed by the Centers for Medicare and Medicaid Services (CMS). Approaches 3 and 4 build on the approaches developed by CMS by including all inpatient hospital claims in the OT file and excluding codes related to delivery services for infants, respectively. Approach 5 applied Approach 4 to only the IP file.

PRINCIPAL FINDINGS

Approach 4, which included all inpatient hospital claims in the OT file and excluded codes related to infants to identify deliveries, achieved the best match of birth counts relative to CDC birth record data, identifying 1,656,794 live births-a national overcount of 3.6%. Approaches 1 and 3 resulted in larger overcounts of births (20.5% and 4.5%), while Approaches 2 and 5 resulted in undercounts of births (-3.4% and -6.8%).

CONCLUSIONS

Including claims from both the IP and OT files, and excluding codes unrelated to the delivery episode and those specific to services rendered to infants improves accuracy of live birth identification in the TAF data.

Interbirth Intervals of Immigrant and Refugee Women in the United States: A Cross-Sectional Study

Background and Objective

Despite guidelines recommending an interval of at least 18-24 months between a live birth and the conception of the next pregnancy, nearly one-third of pregnancies in the United States are conceived within 18 months of a previous live birth. The purpose of this study was to examine the associations between multiple immigration-related variables and interbirth intervals among reproductive-aged immigrant and refugee women living in the United States.

Methods

This was a cross-sectional, quantitative study on the sexual and reproductive health (SRH) of reproductive-aged immigrant and refugee women in the United States. The data were collected via an online survey administered by Lucid LLC. We included data on women who had complete information on nativity and birth history in the descriptive analysis (n = 653). The exposure variables were immigration pathway, length of time since immigration, and country/region of birth. The outcome variable was interbirth interval (≤18, 19-35, or ≥36 months). We used multivariable ordinal logistic regression, adjusted for confounders, to determine the factors associated with having a longer interbirth interval among women with second- or higher-order births (n = 245).

Results

Approximately 37.4% of study participants had a short interbirth interval. Women who immigrated to the United States for educational (aOR = 4.57; 95% CI, 1.57-9.58) or employment opportunities (aOR = 2.27; 95% CI, 1.07-5.31) had higher odds of reporting a longer interbirth interval (19-35 or ≥36 months) than women born in the United States. Women born in an African country had 0.79 times the odds (aOR = 0.79; 95% CI, 0.02-0.98) of being in a higher category of interbirth interval.

Conclusion and Global Health Implications

Although all birthing women should be counseled on optimal birth spacing through the use of postpartum contraception, immigrant and refugee women would benefit from further research and policy and program interventions to help them in achieving optimal birth spacing. SRH research in African immigrant and refugee communities is especially important for identifying ameliorable factors for improving birth spacing.

Intentionally or Ambivalently Risking a Short Interpregnancy Interval: Reproductive-Readiness Factors in Women's Postpartum Non-Use of Contraception

A focus of research on short interpregnancy intervals (IPI) has been on young disadvantaged women whose births are likely to be unintended. Later initiation of family formation in the United States and other high-income countries points to the need to also consider a woman's attributes indicative of readiness for purposefully accelerated family formation achieved through short IPIs. We test for whether factors indicating "reproductive readiness"-including being married, being older, and having just had a first birth or a birth later than desired-predict a woman's non-use of contraception in the postpartum months. We also test for whether this contraceptive non-use results explicitly from wanting to become pregnant again. The data come from the 2012-2015 Pregnancy Risk Assessment Monitoring System, representing women who recently gave birth in any of 35 U.S. states and New York City (N = 120,111). We find that these reproductive-readiness factors are highly predictive of women's postpartum non-use of contraception because of a stated desire to become pregnant and are moderately predictive of contraceptive non-use without an explicit pregnancy intention. We conclude that planning for, or ambivalently risking, a short IPI is a frequent family-formation strategy for women whose family formation has been delayed. This is likely to become increasingly common as family formation in the United States is initiated later in the reproductive life course.

Outcome-dependent associations between short interpregnancy interval and offspring psychological and educational problems: a population-based quasi-experimental study

Background

Causal interpretation of associations between short interpregnancy interval (the duration from the preceeding birth to the conception of the next-born index child) and the offspring's psychological and educational problems may be influenced by a failure to account for unmeasured confounding.

Methods

Using population-based Swedish data from 1973-2009, we estimated the association between interpregnancy interval and outcomes [autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), severe mental illness, suicide attempt, criminality, substance-use problem and failing grades] while controlling for measured covariates. We then used cousin comparisons, post-birth intervals (the interval between the second- and third-born siblings to predict second-born outcomes) and sibling comparisons to assess the influence of unmeasured confounding. We included an exploratory analysis of long interpregnancy interval.

Results

Interpregnancy intervals of 0-5 and 6-11 months were associated with higher odds of outcomes in cohort analyses. Magnitudes of association were attenuated following adjustment for measured covariates. Associations were eliminated for ADHD, severe mental illness and failing grades, but maintained magnitude for ASD, suicide attempt, criminality and substance-use problem in cousin comparisons. Post-birth interpregnancy interval and sibling comparisons suggested some familial confounding. Associations did not persist across models of long interpregnancy interval.

Conclusions

Attenuation of the association in cousin comparisons and comparable post-birth interval associations suggests that familial genetic or environmental confounding accounts for a majority of the association for ADHD, severe mental illness and failing grades. Modest associations appear independently of covariates for ASD, suicide attempt, criminality and substance-use problem. Post-birth analyses and sibling comparisons, however, show some confounding in these associations.

Trends in socioeconomic inequalities in child undernutrition: Evidence from Nigeria Demographic and Health Survey (2003 - 2013)

OBJECTIVE

The aim of this study was to examine the trend in socioeconomic inequalities in child undernutrition in Nigeria.

METHODS

The study analysed cross-sectional data from the Nigeria Demographic and Health Survey (NDHS) 2003 to 2013. The outcome variables were stunting, wasting and underweight among children under-five years. The magnitude of child undernutrition in Nigeria was estimated via a concentration index, and the socioeconomic factors contributing to child undernutrition over time were determined using the decomposition method.

RESULTS

The concentration index showed an increase in childhood wasting and underweight in Nigeria over time. The socioeconomic factors contributing to the increase in child undernutrition were: child's age (0-23 months), maternal education (no education), household wealth index (poorest household), type of residence (rural) and geopolitical zone (North East, North West).

CONCLUSIONS

To address child undernutrition, there is a need to improve maternal education and adopt effective social protection policies especially in rural communities in Nigeria.

The Association of Inadequate and Intensive Prenatal Care With Maternal, Fetal, and Infant Outcomes: A Population-Based Study in Manitoba, Canada

OBJECTIVE

Little is known about how prenatal care influences health outcomes in Canada. The objective of this study was to examine the association of prenatal care utilization with maternal, fetal, and infant outcomes in Manitoba.

METHODS

This retrospective cohort study conducted at the Manitoba Centre for Health Policy investigated all deliveries of singleton births from 2004-2005 to 2008-2009 (N = 67 076). The proportion of women receiving inadequate, intermediate/adequate, and intensive prenatal care was calculated. Multivariable logistic regression was used to examine the association of inadequate and intensive prenatal care with maternal and fetal-infant health outcomes, health care use, and maternal health-related behaviours.

RESULTS

The distribution of prenatal care utilization was 11.6% inadequate, 84.4% intermediate/adequate, and 4.0% intensive. After adjusting for sociodemographic factors and maternal health conditions, inadequate prenatal care was associated with increased odds of stillbirth, preterm birth, low birth weight, small for gestational age (SGA), admission to the NICU, postpartum depressive/anxiety disorders, and short interpregnancy interval to next birth. Women with inadequate prenatal care had reduced odds of initiating breastfeeding or having their infant immunized. Intensive prenatal care was associated with reduced odds of stillbirth, preterm birth, and low birth weight and increased odds of postpartum depressive/anxiety disorders, initiation of breastfeeding, and infant immunization.

CONCLUSION

Inadequate prenatal care was associated with increased odds of several adverse pregnancy outcomes and lower likelihood of health-related behaviours, whereas intensive prenatal care was associated with reduced odds of some adverse pregnancy outcomes and higher likelihood of health-related behaviours. Ensuring women receive adequate prenatal care may improve pregnancy outcomes.

Interpregnancy Intervals in a Contemporary Manitoba Cohort: Prevalence of So-Called Suboptimal Intervals and Associated Maternal Characteristics

OBJECTIVE

Short and long interpregnancy intervals (IPIs) have been associated with various adverse outcomes, and a 2016 American College of Obstetricians and Gynecologists' Committee Opinion recommends an optimal IPI of 18 months to 5 years. Descriptive data on the IPI in Canada are lacking. The objective of this study was to examine IPIs in a Manitoba cohort.

METHODS

The study analyzed a subset of records from a larger dataset used to examine the IPI and adverse perinatal outcomes. For that study, Manitoba's Hospital Abstracts data were searched to identify births from 1985 to 2014. Each two consecutive live births to the same mother formed a sibling pair. The IPI was calculated as the interval between the two siblings' births, minus the younger sibling's GA. Information on maternal characteristics was extracted from various datasets housed in the Manitoba Population Research Data Repository. The current analysis examined second and higher-order births between 2010 and 2014. The proportion of suboptimal IPIs was determined and IPIs were cross-tabulated with birth year and maternal subgroups.

RESULTS

More than half of pregnancies were conceived following a suboptimal interval. IPIs of less than 6 months - which have been associated with the highest risk of adverse outcomes - were more prevalent among certain subgroups. These included younger women as well as women who received inadequate prenatal care, smoked or drank alcohol during pregnancy, were low income, or did not graduate from high school.

CONCLUSION

Suboptimal IPIs were common in this Manitoba cohort. Stakeholders should consider whether greater efforts to promote appropriate birth spacing 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 Self-Reported Prenatal Counseling: Does Immigrant Status Matter?

Immigrant women face unique barriers to prenatal care access and patient-provider communication. Yet, few prior studies have examined U.S.-born/immigrant differences in the content of care. The purpose of this study was to investigate the roles of immigrant status, English proficiency and race/ethnicity on the receipt of self-reported prenatal counseling using nationally representative data. We used data from the Early Childhood Longitudinal Study-Birth Cohort (N ≈ 8100). We investigated differences in self-reported prenatal counseling by immigrant status, English proficiency, and race/ethnicity using logistic regression. Counseling topics included diet, smoking, drinking, medication use, breastfeeding, baby development and early labor. In additional analyses, we separately examined these relationships among Hispanic, Mexican and Non-Hispanic (NH) Asian women. Neither immigrant status nor self-reported English proficiency was associated with prenatal counseling. However, we found that being interviewed in a language other than English language by ECLS-B surveyors was positively associated with counseling on smoking (OR, 2.599; 95% CI, 1.229-5.495) and fetal development (OR, 2.408; 95% CI, 1.052-5.507) among Asian women. Race/ethnicity was positively associated with counseling, particularly among NH black and Hispanic women. There is little evidence of systematic overall differences in self-reported prenatal counseling between U.S.-born and immigrant mothers. Future research should investigate disparities in pregnancy-related knowledge among racial/ethnic subgroups.

Within-Family Analysis of Interpregnancy Interval and Adverse Birth Outcomes

OBJECTIVE

To examine associations among interpregnancy interval, the duration from the preceding birth to the conception of the next-born index child, and adverse birth outcomes using designs that adjust for measured and unmeasured factors.

METHODS

In this prospective cohort study, we used population-based Swedish registries from 1973 to 2009 to estimate the associations between interpregnancy interval (referent 18-23 months) and adverse birth outcomes (ie, preterm birth [less than 37 weeks of gestation], low birth weight [LBW; less than 2,500 g], small for gestational age [SGA; greater than 2 SDs below average weight for gestational age]). Analyses included cousin and sibling comparisons and postbirth intervals (ie, the interval between secondborn and thirdborn offspring predicting secondborn outcomes) to address unmeasured familial confounding.

RESULTS

Traditional cohort-wide analyses showed higher odds of preterm birth (adjusted odds ratio [OR] 1.51, 99% CI 1.39-1.63, 5.99% preterm births]) and LBW (adjusted OR 1.25, 99% CI 1.13-1.39, 3.32% LBW) after a short interpregnancy interval (0-5 months) compared with offspring born after an interpregnancy interval of 18-23 months (3.21% preterm births, 1.92% LBW). Except for preterm birth (adjusted OR 1.72, 99% CI 1.26-2.35), associations were attenuated in cousin comparisons. A small association between a short interpregnancy interval and preterm birth remained in sibling comparisons (adjusted OR 1.22, 99% CI 1.11-1.35), but associations with LBW (adjusted OR 0.83, 99% CI 0.74-0.94) and SGA (adjusted OR 0.74, 99% CI 0.64-0.85) reversed direction. For pregnancy intervals of 60 months or more, odds of preterm birth (adjusted OR 1.51, 99% CI 1.43-1.60, 5.07% preterm births), LBW (adjusted OR 1.61, 99% CI 1.50-1.73, 3.43% low-birth-weight births), and SGA (adjusted OR 1.54, 99% CI 1.42-1.66, 2.49% SGA births) were also higher when compared with the reference interval (1.53% SGA). Associations between long interpregnancy interval and adverse birth outcomes remained through cousin and sibling comparisons. Postbirth interval analyses showed familial confounding is present for short interpregnancy intervals, but supported independent associations for long interpregnancy intervals.

CONCLUSION

Familial confounding explains most of the association between a short interpregnancy interval and adverse birth outcomes, whereas associations with long interpregnancy intervals were independent of measured and unmeasured factors.

The impact of postpartum contraception on reducing preterm birth: findings from California

OBJECTIVE

Family planning is recommended as a strategy to prevent adverse birth outcomes. The potential contribution of postpartum contraceptive coverage to reducing rates of preterm birth is unknown. In this study, we examine the impact of contraceptive coverage and use within 18 months of a birth on preventing preterm birth in a Californian cohort.

STUDY DESIGN

We identified records for second or higher-order births among women from California's 2011 Birth Statistical Master File and their prior births from earlier Birth Statistical Master Files. To identify women who received contraceptive services from publicly funded programs, we applied a probabilistic linking methodology to match birth files with enrollment records for women with Medi-Cal or Family Planning, Access, Care, and Treatment Program (PACT) claims. The length of contraceptive coverage was determined through applying an algorithm based on the specified method and the quantity dispensed. Preterm birth was defined as a birth occurring <37 weeks' gestation, and calculated from the medical record. We further examined differences in preterm birth using subcategories defined by the World Health Organization: extremely preterm (<28 weeks); very preterm (28 to <32 weeks); and moderate to late preterm (32 to <37 weeks). We built a multivariable regression model to examine the effect of contraceptive coverage on the odds of a preterm birth and control for key covariates.

RESULTS

The cohort consisted of 111,948 women who were seen at least once by a Medi-Cal or Family PACT provider within 18 months of delivery. Of the cohort, 9.75% had a preterm birth. Contraceptive coverage was found to be protective against preterm birth. For every month of contraceptive coverage, odds of a preterm birth <37 weeks decrease by 1.1% (odds ratio, 0.989; 95% confidence interval, 0.986-0.993).

CONCLUSION

Improving postpartum contraceptive use has the potential to reduce preterm births.

Short and long interpregnancy intervals: correlates and variations by pregnancy timing among U.S. women

CONTEXT

Short and long interpregnancy intervals are associated with adverse health outcomes. Little is known about the correlates of short and long interpregnancy intervals in the general population, and whether correlates vary by pregnancy intention.

METHODS

Data on 10,236 pregnancies following a live birth were drawn from the 1995, 2002 and 2006-2010 waves of the National Survey of Family Growth. Logistic regression was used to assess characteristics associated with women's reporting short interpregnancy intervals (less than 12 months) and long intervals (greater than 60 months). Analyses were stratified by whether women considered their pregnancies well timed or mistimed.

RESULTS

Thirty-one percent of pregnancies following short intervals and 47% following long intervals were well timed. Among well-timed pregnancies only, the odds of short intervals were elevated if women had been 35 or older, rather than aged 20-29, at last pregnancy (odds ratio, 2.3); if their prior infant had died (10.6); or if they had wanted their prior pregnancy sooner than it had occurred (2.2). Overall, the odds of long intervals were higher among minority groups than among whites (1.4-1.6) and were lower among women who had been 30 or older at prior pregnancy than among those who had been in their 20s (0.1-0.5); they increased with level of family income. Correlates of long intervals generally varied little by intention.

CONCLUSIONS

Although the majority of pregnancies at short intervals are unintended, specific subsets of women have elevated odds of intending short interpregnancy intervals.

Outreach and integration programs to promote family planning in the extended postpartum period

BACKGROUND

WHO recommends birth spacing to improve the health of the mother and child. One strategy to facilitate birth spacing is to improve the use of family planning during the first year postpartum.

OBJECTIVES

To determine from the literature the effectiveness of postpartum family-planning programs and to identify research gaps.

SEARCH STRATEGY

PubMed and the Cochrane Central Register of Controlled Trials were systematically searched for articles published between database inception and March 2013. Abstracts of conference presentations, dissertations, and unpublished studies were also considered.

SELECTION CRITERIA

Published studies with birth spacing or contraceptive use outcomes were included.

DATA COLLECTION AND ANALYSIS

Standard abstract forms and the US Preventive Services Task Force grading system were used to summarize and assess the quality of the evidence.

MAIN RESULTS

Thirty-four studies were included. Prenatal care, home visitation programs, and educational interventions were associated with improved family-planning outcomes, but should be further studied in low-resource settings. Mother-infant care integration, multidisciplinary interventions, and cash transfer/microfinance interventions need further investigation.

CONCLUSIONS

Programmatic interventions may improve birth spacing and contraceptive uptake. Larger well-designed studies in international settings are needed to determine the most effective ways to deliver family-planning interventions.

Effects of prenatal care on child health at age 5

The broad goal of contemporary prenatal care is to promote the health of the mother, child, and family through the pregnancy, delivery, and the child's development. Although the vast majority of mothers giving birth in developed countries receive prenatal care, past research has not found compelling evidence that early or adequate prenatal care has favorable effects on birth outcomes. It is possible that prenatal care confers health benefits to the child that do not become apparent until after the perinatal period. Using data from a national urban birth cohort study in the US, we estimate the effects of prenatal care on four markers of child health at age 5-maternal-reported health status, asthma diagnosis, overweight, and height. Prenatal care, defined a number of different ways, does not appear to have any effect on the outcomes examined. The findings are robust and suggest that routine health care encounters during the prenatal period could potentially be used more effectively to enhance children's health trajectories. However, future research is needed to explore the effects of prenatal care on additional child health and developmental outcomes as well as the effects of preconceptional and maternal lifetime healthcare on child health.