(671) Neonatal outcomes in fetuses with resolved growth restriction

Friday, January 31, 2025

10:30 AM – 12:30 PM

Submitting Author and Presenting Author(s)

Aleksandra Polic, MD

Assistant Professor
University of Pittsburgh Medical Center

Coauthor(s)

TM

Trey McGonigle, MS

Vanderbilt University Medical Center
Nashville, Tennessee, United States
SH

Shi Huang, PhD

Vanderbilt University Medical Center
Nashville, Tennessee, United States
CP

Catherine Phillips, MD

Vanderbilt University Medical Center
Nashville, Tennessee, United States
MG

Matthew Grace, MD

Vanderbilt University Medical Center
Nashville, Tennessee, United States

Objective: Fetal growth restriction (FGR) is associated with neonatal morbidity and mortality, but 17% of fetuses with FGR will return to normal growth prior to delivery (resolved FGR, rFGR). Neonatal outcomes of this group have not been studied, and insufficient data exist to guide management. The aim of this study was to compare neonatal outcomes of pregnancies complicated by rFGR to pregnancies with no history of FGR.

Study Design: This was a retrospective cohort study of live, term singleton deliveries without known or suspected structural or genetic abnormalities from 2018-2023 at a tertiary medical center. The exposed cohort had an ultrasound diagnosis of FGR (either by AC or EFW < 10^th percentile) followed by resolution of FGR on a subsequent ultrasound preceding delivery. Maternal demographics, clinical characteristics and delivery outcomes were compared by FGR status (no FGR, FGR and rFGR) at the time of delivery. We fit separate logistic regression models to estimate the association between rFGR and NICU admission, hypoxic ischemic encephalopathy (HIE), and neonatal death, adjusting for confounders. Birth weight, length of hospital stay, and APGAR scores were modeled using linear and proportional odds ordinal regression models.

Results: A total of 11,957 pregnancies were analyzed, of which 393 were complicated by rFGR. No differences were observed between rFGR and no FGR patients in rates of hypertensive disorders, diabetes, gestational age at delivery, or mode of delivery (Table 1). Compared to no FGR, birth weights in the rFGR cohort were lower by 366g (95% CI -422.37, -310.39; p< 0.001). No other significant effects of rFGR were observed in any of the neonatal outcomes assessed (Table 2). Although not statistically significant, the direction of the effect suggests that neonates with rFGR (vs. no FGR) may have increased odds of NICU admission, HIE, neonatal death, and longer duration of hospital stay.

Conclusion: When compared to pregnancies not complicated by FGR, the diagnosis of rFGR did not increase the risk of adverse neonatal outcomes in this cohort.