Maternal and neonatal complications in women with medical comorbidities and preeclampsia

Objectives: To evaluate how medical comorbidities - chronic hypertension, pre-gestational or gestational diabetes and obesity - influence maternal and neonatal complications from preeclampsia. Study design: We undertook a retrospective cohort study of women delivering in Victoria, Australia, between 2009 and 2017. We compared the likelihood of having a maternal complication before delivery or neonatal complication after birth between women with and without comorbidities. We used causal mediation analysis for neonatal outcomes to separate the effects of comorbidities and of prematurity on morbidity. Main outcome measures: Pregnancy complications (eclampsia; haemolysis, elevated liver enzymes, low platelets syndrome; placental abruption; stillbirth) and neonatal complications (respiratory distress syndrome; neonatal sepsis; a 5-minute APGAR < 5; neonatal intensive care unit admission). Results: Women with comorbidities delivered at a median (interquartile range) of 37.0 (36.0-39.0) weeks gestation, earlier than women without comorbidities (38.0 (36.0-39.0) weeks, p < 0.001). Women with comorbidities were less likely than those without to suffer any pregnancy complication prior to delivery (adjusted relative risk 0.78, 95% confidence interval 0.72-0.86); however, their neonates suffered more respiratory distress syndrome (aRR 1.43, 95% CI 1.31-1.57), neonatal sepsis (aRR 1.42, 95% CI 1.17-1.72) and NICU admission (aRR 1.37, 95% CI 1.23-1.53). Earlier delivery was a major contributor to worse neonatal outcomes. Conclusions: Medical comorbidities are associated with earlier delivery among women with preeclampsia. This is associated with fewer maternal complications, but worse neonatal outcomes.