Adverse Maternal and Perinatal Outcomes: A Comparison of United States- and Foreign-Born Women [32C

Abstract

INTRODUCTION: Despite significant socio-economic disadvantages, improved perinatal outcomes have been observed among foreign-born women relative to the native population in multiple countries. The current study aims to assess perinatal outcomes of United States (U.S.)- and foreign-born women in Boston, Massachusetts; and investigate how these differences are impacted by socio-demographic risk factors. METHODS: We analyzed singleton, index pregnancies (n=11,124) among women delivering at Boston Medical Center between January 2010 and December 2015. Outcomes included preterm birth, cesarean delivery, hypertensive disorders, abnormal glucose tolerance, premature rupture of membranes (PROM), fetal growth restriction, low birth weight at term (LBW, less than 2500g), neonatal intensive care unit (NICU) admission and intrauterine fetal demise (IUFD). Multivariate regression was used to control for maternal age, race, ethnicity, insurance coverage and tobacco use. RESULTS: Preterm birth, hypertensive disorders, PROM, LBW, NICU admission and fetal growth restriction were more common among U.S.-born women and their neonates (P less than .000). Foreign-born women were more likely to have abnormal glucose tolerance (P equals .008). Controlling for maternal characteristics eliminated the effect of maternal birthplace on fetal growth restriction (adjusted OR 0.98) and abnormal glucose tolerance (adjusted OR 1.06), but did not modify the effect on other study outcomes. CONCLUSION: U.S.-born women are at higher risk of adverse perinatal outcomes than foreign-born women. This increased risk persists for many outcomes even after controlling for confounders. As the immigrant population in the U.S. grows, understanding the social and physiologic determinants of these differences may guide targeted interventions critical for improving overall maternal and child health.