(878) Association Between Hypertensive Disorders and Neonatal Mortality Among Periviable Deliveries

Friday, January 31, 2025

10:30 AM – 12:30 PM

Submitting Author and Presenting Author(s)

Peeraya S. Sawangkum, MD (she/her/hers)

Maternal Fetal Medicine Fellow
Department of Obstetrics and Gynecology, University of South Florida
Tampa, Florida, United States

Coauthor(s)

JT

Jean Paul P. Tanner, MPH, PhD

Assistant Professor
Department of Obstetrics and Gynecology, University of South Florida
Tampa, Florida, United States
JS

Jason L. Salemi, MPH, PhD

Professor
Department of Obstetrics and Gynecology, University of South Florida
Tampa, Florida, United States
Jose R. Duncan, MD (he/him/his)

Associate Professor
Department of Obstetrics and Gynecology, University of South Florida, Morsani College of Medicine
Tampa, Florida, United States

Objective: The objective of this study was to determine the association between hypertensive disorders of pregnancy (including chronic hypertension, gestational hypertension, and pre-eclampsia) and 1-year survival among periviable neonates delivered at 22w0d-25w6d.

Study Design: This is a retrospective cohort study using a maternal-infant linked database of live births in the state of Florida from 2006 to 2019. Singleton deliveries of infants born at 22w0d to 25w6d in which neonatal resuscitation was attempted were included. Adjusted hazard ratios (aHRs) were estimated to compare survival across exposures groups, overall and by week of gestation.

Results: Of the 6,898 periviable deliveries identified during the study period, 1,405 (20.4%) were affected by a hypertensive disorder. Patients affected with hypertension were also more likely to be of advanced maternal age, overweight/obese, non-Hispanic Black, have pre-existing diabetes, have connective tissue / autoimmune conditions, and have a diagnosis of fetal growth restriction. Among all periviable births, hypertensive disorders were associated with increased risk of death during the first year of life (aHR 1.24, 95% CI 1.13-1.38). However, when stratified by gestational age week, hypertensive disorder had no effect on risk of death at 1-year among 22- and 23-week neonates (aHR 0.73, 95% CI 0.50-1.07 and aHR 1.17, 95% CI 0.96-1.43 respectively), but increased risk of death among 24- and 25- week neonates (aHR 1.37, 95% CI 1.16-1.62 and aHR 1.41, 95% CI 1.17-1.69 respectively).

Conclusion: This study demonstrates that hypertensive disorders of pregnancy are associated with increased neonatal mortality among periviable neonates born at 24- and 25-weeks gestation, but not at 22- and 23-weeks gestation. These findings may help guide perinatologists when counseling patients in the periviable period.