Abstract P141: Infant Mortality Risk In Hypertensive Disorders Of Pregnancy

Abstract

Introduction: Hypertensive disorders of pregnancy (HDP) increase the risk of infant and maternal morbidity and mortality, disproportionately affecting racial and ethnic minority groups. Less is known about disparities in infant mortality by mother’s HDP status. We assessed the relationships between HDP and pre-pregnancy hypertension and other pregnancy and delivery characteristics with infant mortality. Methods: This retrospective cohort study included 667,359 live, singleton deliveries (mother’s race/ethnicity: non-Hispanic White [NHW; 56.5%], non-Hispanic Black [NHB; 32.2%)], Hispanic [9.0%], other race/ethnicity [2.2%]) in South Carolina (2004-2016) to women aged 12-49 years. HDP (pre-eclampsia, eclampsia, gestational hypertension) and pre-pregnancy hypertension were defined by hospitalization/emergency department (ED) visit data or birth certificates. Infant mortality within one year (n=2,431) was defined by death certificates. Logistic regression models controlled for covariates. Results: Deliveries to women with pre-pregnancy hypertension with superimposed HDP (2.1%), HDP (16.9%), pre-pregnancy hypertension without superimposed HDP (0.3%), and neither condition (80.6%) were described. Infant mortality was increased for women with HDP with and without pre-pregnancy hypertension. Also associated with higher odds of infant mortality were NHB mothers, with high school education or less, Medicaid, higher pre-pregnancy BMI, no prenatal care, increasing number of prior pregnancies, prior Cesarean section, prior preterm birth, and women smoking during pregnancy; with the odds lower for increasing maternal age, Hispanic mothers, and female sex of baby. Discussion: The odds of infant mortality were increased 48% in women with HDP and 83% in women with both HDP and pre-pregnancy hypertension than women with neither condition after adjusting for pregnancy and delivery characteristics. Future studies are needed to identify social or other factors contributing to differences.