Selection bias in prenatal care use by Medicaid recipients

Maternal and child health journal, 2017

Objectives Pennsylvania's maternal mortality, infant mortality, and preterm birth rates rank 24th, 35th, and 25th in the country, and are higher among racial and ethnic minorities. Provision of prenatal and postpartum care represents one way to improve these outcomes. We assessed the extent of disparities in the provision and timeliness of prenatal and postpartum care for women enrolled in Pennsylvania Medicaid. Methods We performed a cross-sectional evaluation of representative samples of women who delivered live births from November 2011 to 2015. Our outcomes were three binary effectiveness-of-care measures: prenatal care timeliness, frequency of prenatal care, and postpartum care timeliness. Pennsylvania's Managed Care Organizations (MCOs) were required to submit these outcomes to the state after reviewing administrative and medical records through a standardized, validated sampling process. We assessed for differences in outcomes by race, ethnicity, region, year, and MCO...

Journal of Clinical Medicine, 2019

Little is known about the associations of Adequacy of Prenatal Care Utilization (APNCU) index with small-for-gestational-age (SGA) infants and preterm births. This study investigated the association between the Adequacy of Prenatal Care Utilization (APNCU) index in relation to small-for-gestational-age (SGA) infants and preterm births. We used data from 212,050 pregnant women from the Pregnancy Risk Assessment Monitoring System (PRAMS) between 2004 and 2011. Multivariable logistic regression analyses were performed to examine the effect of the APNCU index on SGA infants and preterm births after controlling for maternal sociodemographic factors. Women who received adequate-plus prenatal care in reference to adequate prenatal care had increased odds for delivering SGA infants (adjusted odds ratio (AOR) = 1.08, 95% confidence interval (CI) = 1.03–1.15). Women with 9–11 prenatal care visits had increased odds of delivering SGA infants (AOR = 1.07, 95% CI = 1.02–1.14) compared to those w...

Social Forces, 2001

This article examines the effects of various demographic and biomedical covariates on the level of prenatal care utilization (Kotelchuck's APNCU) received by U.S. resident women giving birth between the years 1989 and 1991 (N10 million). Results from multinomial logistic regression models for thirteen different race/ethnic groups show a strikingly consistent pattern of effects between covariates and the level of prenatal care obtained. Across race/ethnic groups, mothers that were young, low-educated, unmarried, high-parity, and smoked were most at risk of receiving no or inadequate prenatal care. Those women who had experienced a previous preterm or small-for-gestational-age birth or prior infant loss were more likely to receive more extensive ("intensive") care. Presence of a medical risk during pregnancy increased the odds of no/inadequate care and of intensive care. These results support the view that prenatal care intervention strategies can be expected to affect a...

2020

This thesis investigated the connection between socioeconomic status, healthcare coverage, and birth outcomes. The research question that was posed specifically looked at twenty perinatal services that states covered under Medicaid to varying degrees to see their association, if any, with premature birth rates and low birthweight rates. State-level and Mississippi county-level data were compiled regarding preterm birth rates, low birthweight rates, presumptive eligibility adoption, and coverage of twenty different perinatal services. Using these data, the correlation between state Medicaid expansion status and birth outcomes was first calculated in order to determine if variation in birth outcomes was associated with expanded Medicaid coverage. After this, the relationship between birth outcomes and poverty was determined at both the state level and the Mississippi county level. The research found that poverty had a very positive correlation with high rates of poor birth outcomes and that state-level coverage was minimally correlated with birth outcomes. This study concluded by calling for further research into the Medicaid system, preventative care models for Medicaid, or systemic reform to the healthcare delivery system. AN EXAMINATION OF […] PERINATAL SERVICES AND BIRTH OUTCOMES iv ACKNOWLEDGEMENTS I would first like to thank Dr. John Green for all of the time and effort he has poured into my writing process throughout my undergraduate career. I would also like to thank my committee of readers, Dr. Lefmann and Dr. Dellinger for all of the editing advice and for being willing to take on another thesis defense. I would lastly like to thank my family for teaching me the importance of education and for supporting me wholeheartedly in my college endeavors.

JAMA Network Open, 2021

IMPORTANCE Policy makers are considering insurance expansions to improve maternal health. The tradeoffs between expanding Medicaid or subsidized private insurance for maternal coverage and care are unknown. OBJECTIVE To compare maternal coverage and care by Medicaid vs marketplace eligibility. DESIGN, SETTING, AND PARTICIPANTS A retrospective cohort study using a difference-indifference research design was conducted from March 14, 2020, to April 22, 2021. Maternal coverage and care use were compared among women with family incomes 100% to 138% of the federal poverty level (FPL) residing in 10 Medicaid expansion sites (exposure group) who gained Medicaid eligibility under the Affordable Care Act and in 5 nonexpansion sites (comparison group) who gained marketplace eligibility before (2011-2013) and after (2015-2018) insurance expansion implementation. Participants included women aged 18 years or older from the 2011-2018 Pregnancy Risk Assessment Monitoring System survey. EXPOSURES Eligibility for Medicaid or marketplace coverage under the Affordable Care Act. MAIN OUTCOMES AND MEASURES Outcomes included coverage in the preconception and postpartum periods, early and adequate prenatal care, and postpartum checkups and effective contraceptive use. RESULTS The study population included 11 432 women age 18 years and older (32% age 18-24 years, 33% age 25-29 years, 35% age Ն30 years) with incomes 100% to 138% FPL: 7586 in a Medicaid state (exposure group) and 3846 in a nonexpansion marketplace state (comparison group). Women in marketplace states were younger, had higher educational level and marriage rates, and had less racial and ethnic diversity. Medicaid relative to marketplace eligibility was associated with increased Medicaid coverage (20.3 percentage points; 95% CI, 12.8 to 30.0 percentage points), decreased private insurance coverage (−10.8 percentage points; 95% CI, −13.3 to −7.5 percentage points), and decreased uninsurance (−8.7 percentage points; 95% CI, −20.1 to −0.1 percentage points) in the preconception period, increased postpartum Medicaid (17.4 percentage points; 95% CI, 1.7 to 34.3 percentage points) and increased adequate prenatal care (4.4 percentage points; 95% CI, 0.1 to 11.0 percentage points) in difference-indifference models. No evidence of significant differences in early prenatal care, postpartum checkups , or postpartum contraception was identified. CONCLUSIONS AND RELEVANCE In this cohort study, eligibility for Medicaid was associated with increased Medicaid, lower preconception uninsurance, and increased adequate prenatal care use. The lower rates of preconception uninsurance among Medicaid-eligible women suggest that women with low incomes were facing barriers to marketplace enrollment, underscoring the potential (continued) Key Points Question How does preconception and postpartum coverage and care use compare among women with low incomes gaining eligibility for Medicaid vs marketplace coverage? Findings In this cohort study of 11 432 women with low incomes, Medicaid eligibility relative to marketplace eligibility was associated with significantly increased Medicaid coverage (20.3 percentage points), decreased private insurance coverage (−10.8 percentage points), and decreased uninsurance (−8.7 percentage points) in the preconception period. It was also associated with increased postpartum Medicaid (17.4 percentage points) and increased adequate prenatal care (4.4 percentage points) but not with significant changes in early prenatal care, postpartum checkups, or postpartum contraception. Meaning The finding of lower rates of preconception uninsurance among Medicaid-eligible women in this study suggests that women with low incomes were facing barriers to marketplace enrollment.

1997

The purpose of this research was to determine how much of the variance in birthweight can be explained by socioeconomic status and utilization of prenatal care in Blacks and Whites. Rather than defi ning race in genetic terms, race was understood here as a social construction. The methodological approach was an analysis of the National Survey of Family Growth Cycle IV, 1988. The fi rst, singleton, live birth for each interviewed woman was included, resulting in a sample of 911 women, of whom 313 were Black women and 598 White women. Consistent with previous research, Black mothers were twice as likely to have a low birthweight infant (1 1.8%) compared to White women (6%). In the total sample race, vii marital status, and income were correlated with birthweight. Multiple regression analysis was used to examine how much of the variance in birthweight is explained by socio economic factors and utilization of prenatal care. The model explained 5% of the variance in birthweight. Race and education were the only two factors that significantly explained variance in birthweight in this model. The findings failed to support the hypothesis that socioeconomic status and utilization of prenatal care would explain a significant amount of the variance in birthweight. The variables included in the model did not explain variance in birthweight for either Black women, or White women.

Journal of Political Economy, 1996

A key question for health care reform in the U.S. is whether expanded health insurance eligibility will lead to improvements in health outcomes. We address this question in the context of dramatic expansions in the Medicaid eligibility for pregnant women that took place duringthe 1980s. We build a detailed simulation model of each state's Medicaid policy during the 1979-1990 period, and use this model to estimate 1) the effect of changes in the rules on the eligibility of pregnant women for Medicaid, and 2) the effect of Medicaid eligibility changes on birth outcomes in aggregate Vital Statistics data.

Pediatrics, 2016

Perinatal outcomes have improved in developed countries but remain poor for disadvantaged populations. We examined whether an unconditional income supplement to low-income pregnant women was associated with improved birth outcomes. This study included all mother-newborn pairs (2003-2010) in Manitoba, Canada, where the mother received prenatal social assistance, the infant was born in the hospital, and the pair had a risk screen (N = 14 591). Low-income women who received the income supplement (Healthy Baby Prenatal Benefit [HBPB], n = 10 738) were compared with low-income women who did not receive HBPB (n = 3853) on the following factors: low birth weight, preterm, small and large for gestational age, Apgar score, breastfeeding initiation, neonatal readmission, and newborn hospital length of stay (LOS). Covariates from risk screens were used to develop propensity scores and to balance differences between groups in regression models; γ sensitivity analyses were conducted to assess se...

Journal of Clinical Epidemiology, 2002

A recent, nationwide study of 54 million births reported increasing trends toward more prenatal resource utilization from 1981 to 1995, when other indicators have shown worsening trends in birth outcomes. The Adequacy of Prenatal Care Utilization (APNCU) Index was used to measure resource utilization, but the Index appears to be biased because women grouped in the intensive category have the highest rates of low birth weight (LBW). The objective of this paper is to provide a systematic examination of the Index and to uncover biases that may preclude its use in analyzing the association between resource utilization and birth outcomes. This is a cross-sectional study including all singleton live births in 1993 through 1996 ( n ϭ 591,403) in Ohio. Birth certificate data are used to derive the Index, which categorizes women as follows: Adequate Plus (A ϩ ), Adequate , Intermediate , and Inadequate. The Index is based on the ratio of observed to expected (O/E) number of prenatal visits. The expected number of visits is based on the American College of Obstetricians and Gynecologists (ACOG) recommendations. The Index also considers the month of initiation of prenatal care. The outcome measures are low birth weight (LBW) and small-for-gestational age (SGA). The LBW rate is 11.8% in the (A ϩ ) category, compared to 9.4% in the Inadequate category, and 3.3% and 3.5% in each of the Intermediate and Adequate categories, respectively. Preterm births are disproportionately represented in the (A ϩ ) category: 61.2% of births prior to 37 weeks are (A ϩ ), whereas only 18.9% of term births are (A ϩ ). This apparent bias results from the fact that the ACOG schedule of prenatal visits allocates nearly one third of the total visits to the last 4-5 weeks of gestation. A shorter gestational age implies fewer number of expected visits, a smaller denominator in the O/E ratio, and O/E ratios exceeding 100% by large margins. In fact, the observed number of visits exceeds the expected number of visits by only one or two in 40.1% of all births grouped in the (A ϩ ) category. Consequently, the Index yields misleading results indicating that women grouped in the (A ϩ ) category (or O/E ratios Ͼ 110%) are most likely to deliver LBW infants. Contrary to the results obtained through the APNCU Index, our gestational age-specific analysis showed that increasing number of prenatal visits is associated with improved birth outcomes. We recommend that the use of the APNCU Index to study the association between prenatal resource utilization and LBW be discontinued.

Health Affairs, 2020

The federal Strong Start for Mothers and Newborns initiative supported alternative approaches to prenatal care, enhancing service delivery through the use of birth centers, group prenatal care, and maternity care homes. Using propensity score reweighting to control for medical and social risks, we evaluated the impacts of Strong Start's models on birth outcomes and costs by comparing the experiences of Strong Start enrollees to those of Medicaid-covered women who received typical prenatal care. We found that women who received prenatal care in birth centers had lower rates of preterm and low-birthweight infants, lower rates of cesarean section, and higher rates of vaginal birth after cesarean than did the women in the comparison groups. Improved outcomes were achieved at lower costs. There were few improvements in outcomes for participants who received group prenatal care, although their costs were lower in the prenatal period, and no improvements in outcomes for participants in maternity care homes.