Adverse maternal and neonatal outcomes among women with preeclampsia with severe features <34 weeks gestation with versus without comorbidity.

Objectives: To determine adverse maternal and neonatal outcomes among women with preeclampsia with severe features who delivered <34 weeks comparing those with versus without a comorbid condition.

Study Design: A retrospective analysis from the U.S. Consortium on Safe Labor Study of deliveries <34 weeks with preeclampsia with severe features. We examined the association of each comorbid condition versus none with adverse maternal and neonatal outcomes. The comorbidities (not mutually exclusive) were chronic hypertension, pregestational diabetes, gestational diabetes, twin gestation, and fetal growth restriction.

Main Outcomes: Maternal outcome: eclampsia, thromboembolism, ICU admission, and/or death; and neonatal outcome: intracranial/periventricular hemorrhage, hypoxic-ischemic encephalopathy/periventricular leukomalacia, stillbirth, and/or perinatal death.

Results: Among 2217 deliveries, 50% had a comorbidity, namely chronic hypertension (30%), pregestational diabetes (8%), gestational diabetes (8%), twin gestation (10%), and fetal growth restriction (7%). Adverse maternal and neonatal outcomes occurred in 10% and 12% of pregnancies, respectively. Pregnancies with preeclampsia with severe features delivered <34 weeks complicated by gestational diabetes (adjusted risk difference, aRD: -4.9%, 95%CI: -9.11 to -0.71), twin gestation (aRD: -5.1%, 95%CI: -8.63 to -1.73), and fetal growth restriction (aRD: -4.7%, 95%CI: -7.96 to -1.62) were less likely to result in adverse maternal outcome compared to pregnancies without comorbidity, but not chronic hypertension and pregestational diabetes. A pregnancy complicated by fetal growth restriction (aRD: 12.2%, 95%CI: 5.48 to 19.03) was more likely to result in adverse neonatal outcome, but not other comorbid conditions.

Conclusions: Preeclampsia with severe features <34 weeks complicated by comorbidity was generally not associated with an increased risk of adverse maternal and neonatal outcomes, with the exception of fetal growth restriction.