Background: Gastroschisis patients are commonly small for gestational age (SGA, birth weight [BW] < 10th centile). However, the extent, symmetry and causes of that growth restriction remain controversial.
Methods: We compared BW, crown-heel length (LT), occipitofrontal circumference (OFC) and ponderal index (PI) in 179 gastroschisis cases and 895 matched controls by univariate and multiple regression. Fetal ultrasounds (N = 80) were reviewed to determine onset of growth restriction. Placental histology was examined in 31 gastroschisis patients whose placental tissue was available and in 29 controls.
Results: Gastroschisis cases weighed less than controls (BW = 2400 ± 502 g vs. 2750 ± 532 g, p < 0.001) and their BW frequency curve was shifted to the left, indicating lower BW as a group compared to controls (p < 0.001 by Kolmogorov-Smirnov test). BW differences varied from -148 g at 33 weeks to -616 g at 38 weeks gestation. Intrauterine growth restriction was symmetric with gastroschisis patients having a shorter LT (45.7 ± 3.3 vs. 48.4 ± 2.7 cm, p < 0.001), smaller OFC (31.9 ± 1.9 vs. 32.9 ± 1.6 cm, p < 0.001), but larger ponderal index (2.51 ± 0.37 vs. 2.40 ± 0.16, p < 0.001) compared to controls. Gastroschisis patients had a similar reduction in BW (-312 g, 95% confidence interval [CI] = -367, -258) compared to those with chromosomal abnormalities (-239 g, CI = -292, -187). Growth deficits appeared early in the second trimester and worsened as gestation increased. Placental chorangiosis was more common in gastroschisis patients than controls, even after removing all SGA patients (77% vs. 42%, p = 0.02).
Conclusions: Marked, relatively symmetric intrauterine growth restriction is an intrinsic part of gastroschisis. It begins early in the second trimester, and is associated with placental chorangiosis.