Elective preterm birth for fetal gastroschisis

Gastroschisis is an uncommon congenital defect of the anterior abdominal wall that results in herniation of intestinal loops outside the abdominal cavity. Babies with gastroschisis generally do well, but there remains a mortality rate of 5% to 10% and some require prolonged parenteral nutrition and intensive care. Significant injury to the exposed bowel may occur in-utero, and earlier birth may reduce this, improve long-term outcomes and reduce complications, such as necrotising enterocolitis. However, it may also increase complications related to prematurity. There is a lack of published data in this area.

To assess the effects of elective preterm birth for fetal gastroschisis in pregnancies complicated by this condition. The mode of birth may be either vaginal or by caesarean section, but this review is studying only timing, not the route, of birth.

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (16 January 2013).

Individual patient randomised controlled trials of planned preterm birth in pregnancies complicated by fetal gastroschisis, diagnosed by ultrasound scanning in time for preterm birth to be an option, and without other fetal anomalies. The intervention is planned preterm birth, prior to 37 weeks and 0 days' gestation, versus planned later birth, at or after 37 weeks and 0 days' gestation (mode of birth is not part of the intervention).We did not include quasi-randomised controlled trials and cluster trials. Cross-over trials are not appropriate for this condition. Studies that were presented in abstract form only were eligible for inclusion, providing that the population included women with pregnancies affected by fetal gastroschisis, the interventions were defined and the treatment selection was randomised.

Two review authors independently assessed for inclusion the one trial identified as a result of the search strategy and assessed trial quality. Two review authors extracted data and checked it for accuracy.

We included one study, involving 40 infants and 42 women. The trial was underpowered to detect clinically important outcome differences between the two policies. There were no significant benefits or adverse effects of elective preterm birth at 36 weeks' gestation for fetal gastroschisis. The primary outcomes were caesarean section and neonatal survival to discharge. Two babies died after birth but before discharge in the elective (intervention) group versus none in the spontaneous group (risk ratio (RR) 5.00; 95% confidence interval (CI) 0.26 to 98.00; one study, n = 40). Seven women (33%) in the elective group and nine women (43%) in the spontaneous group delivered by caesarean section (RR 0.78; 95% CI 0.36 to 1.70).Similarly, for the secondary outcomes, there were no statistical differences in birthweight, ventilation requirements, necrotising enterocolitis and requirement for repeat surgery between the two groups. None of our prespecified maternal secondary outcomes were reported in the included study.We also examined gestational age at birth as a non-prespecified outcome. There was a difference in gestational age at birth between the two arms of the trial (35.8 weeks (SD 0.7) in the elective group and 36.7 (SD 1.5) in the spontaneous group. Possible reasons for this small mean difference include a trend towards spontaneous preterm birth in pregnancies complicated by fetal gastroschisis.

This review is unable to draw any firm conclusions regarding preterm birth for infants with gastroschisis. It is not possible to say whether the intervention is beneficial or harmful for these babies or their mothers. Only one small trial is included. Further research is needed in this area.