457: Individualized growth assessment in pregnancies complicated by gastroschisis

Abstract

complicated by gastroschisis Sina Haeri, Russell Deter, Padmashree Woodham, Wesley Lee Baylor College of Medicine & Texas Children’s Hospital, Obstetrics & Gynecology, Houston, TX, Mercer School of Medicine & Medical Center of Central Georgia, Obstetrics & Gynecology, Macon, GA OBJECTIVE: Traditional fetal growth assessment has relied on the ultrasound (US) estimated fetal weight (EFW) and comparison with reference ranges. Unfortunately, in pregnancies complicated by gastroschisis, this has led to an overestimation of fetal growth restriction (FGR) due to the defect related abdominal circumference changes. Consequently, our objective was to examine growth using the Individualized Growth Assessment (IGA) with each fetus as its own control. STUDY DESIGN: In this cohort study of pregnancies complicated by gastroschisis, longitudinal US data for biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) were obtained. Second trimester-specific Rossavik models [P c(tk st] for these four anatomical parameters were used to generate expected third-trimester size trajectories with age-specific normal reference ranges. Observed and predicted measurements were compared by percent deviations. Subjects with percent deviation less than the normal range (BPD 0-0%, HC -0.11-0%, AC -0.05-0%, FL -0.27-0%) were classified as not having reached their growth potential for a specific parameter (cases). RESULTS: BPD, HC, and FL parameters exhibited normal size trajectories. For AC, 14 (56%) fetuses reached their individualized growth potential, while 11 (44%) did not. Compared to controls, those with impaired AC growth were more likely to demonstrate non-reassuring fetal heart rate tracing (36% vs. 0%, p 0.03), have a lower BW (2055 / 659 vs. 2886 / 813 grams, p 0.01), and required a longer length of stay (40.3 / 21.1 vs. 25.0 / 15.2 days, p 0.05). Subjects were also categorized based on birthweight as small for gestational age (SGA) vs. normal. SGA status did not predict adverse neonatal outcomes. CONCLUSION: IGA provides an alternative to conventional ultrasound measures of growth by allowing the fetus with gastroschisis to serve as its own control. IGA may serve as a superior tool in identifying fetuses with a tenuous post-natal course and allow for targeted management strategies.