Maternal Pre-eclampsia As a Risk Factor for Necrotizing Enterocolitis

Objective: Similar pro-inflammatory responses are present in pre-eclampsia (PE) and necrotizing enterocolitis (NEC). We hypothesized that maternal PE is an independent risk factor for the development of NEC.

Methods: A retrospective database of all live births (2008-2011) at a tertiary center was constructed. Infant and maternal characteristics were gathered. Babies born to mothers with or without PE were compared. Data were analyzed using Mann-Whitney U, Pearson's χ(2), binary logistic regression and relative risks.

Results: Incidence of NEC was 1.5% in non-PE and 4.6% in the PE group (p < 0.001), but once controlled for gestational age and birth weight, the difference lost statistical significance. PE babies were more frequently preterm (41.4% versus 14.5%, p < 0.001) and had intrauterine growth restriction (IUGR) (10.2% versus 6.3%, p < 0.001). Within preterm babies, 9.0% of non-PE and 10.8% of PE babies developed NEC (p = 0.25). Effect of PE was significant in sub-group of IUGR babies, with NEC in 1.5% of non-PE and 13.6% in PE babies (p < 0.001).

Conclusions: Maternal PE is an independent risk factor for the development of NEC in some sub-groups of babies, most notably with IUGR. Fetal hypoxia caused by abnormal placentation in PE leads to restricted growth, and may be the underlying mechanism that predisposes the newborn to NEC.