Sonographic Detection and Clinical Importance of Growth Restriction in Pregnancies With Gastroschisis

OBJECTIVES The purpose of this study was to estimate the utility of sonography to detect small-for-gestational-age (SGA) neonates in pregnancies with gastroschisis and to evaluate neonatal outcomes according to birth weight percentile. METHODS We conducted a retrospective cohort study of singleton pregnancies with fetal gastroschisis delivered at our hospital between August 1997 and December 2012. Diagnosis of growth restriction was based on estimated fetal weight below the 10th percentile using the nomogram of Hadlock et al (Am J Obstet Gynecol 1985; 151:333-337), evaluated at 4-week intervals throughout gestation and compared with subsequent birth weight, to evaluate the accuracy of sonography to detect and exclude SGA neonates. Pregnancy and neonatal outcomes were evaluated according to birth weight percentile. RESULTS There were 111 births with gastroschisis (6 per 10,000), and one-third (n = 37) had birth weight below the 10th percentile. The sensitivity and negative predictive value of sonography for an SGA neonate both approached 90% by 32 weeks and were approximately 95% thereafter. Detection increased with advancing gestational age (P = .02). The birth weight percentile was not associated with preterm birth, infection, bowel complications requiring surgery, duration of hospitalization, or perinatal mortality. Delayed closure of the gastroschisis defect was more frequent with birth weights at or below the 3rd percentile (P = .03). CONCLUSIONS Sonography reliably identified SGA neonates with gastroschisis in our series, and its utility improved with advancing gestation. Apart from delayed closure of the defect, a low birth weight percentile was not associated with an increased risk of morbidity or mortality in the immediate neonatal period.