Perinatal mortality in pregnancies with omphalocele: data from the Chinese national birth defects monitoring network, 1996-2006

Background: Previous studies on the mortality rate of omphalocele are limited. The risk of death of non-isolated omphalocele and that of cases of omphalocele that are diagnosed prenatally by ultrasound are unclear. This study aimed to estimate the perinatal mortality of pregnancies with omphalocele. This study also examined the potential risk of death of non-isolated omphalocele and that of cases that are prenatally diagnosed by ultrasound. Methods: Data were retrieved from the national birth defects registry in China, for 1996-2006. Multinomial logistic regression was used to calculate the adjusted odds ratios (AORs) and 95% confidence intervals (CIs) between perinatal mortality and selected maternal and fetal characteristics. Results: Among 827 cases of omphalocele, 309 (37.4%) cases resulted in termination of pregnancy and stillbirth, and 124 (15.0%) cases resulted in death in the first 7 days after delivery, yielding a perinatal mortality rate of 52.4% (95% CI: 49.0-55.8%). The late fetal death rate (LFDR) of omphalocele that was diagnosed prenatally by ultrasound was 15.91-fold (AOR: 15.91, 95% CI: 10.18-24.87) higher than that of postnatally diagnosed cases. The LFDR of non-isolated omphalocele was 2.64-fold (AOR: 2.64, 95% CI: 1.62-4.29) higher than that of isolated cases. For the early neonatal death rate, neonates with non-isolated omphalocele had a 2.96-fold (AOR: 2.96, 95% CI: 1.82-4.81) higher risk than isolated cases, but the difference between prenatal ultrasound diagnosis and postnatal diagnosis was not significant. Conclusions: Selected fetal characteristics are significantly associated with the perinatal risk of death from omphalocele. Our findings suggest that improving pregnancy and delivery care, as well as management for omphalocele are important.