Hypertension subtypes and adverse maternal and perinatal outcomes - a retrospective population-based cohort study

This study aims to examine risk of adverse pregnancy outcomes and mothers' characteristics in patients with chronic hypertension, gestational hypertension and preeclampsia.

The study included all births born from women aged 15-45 years, in Lleida, Spain from 2012 to 2018. Pregnancy outcomes were retrieved by regional administrative databases. Logistic regression analysis was used to calculate adjusted odds ratios (OR) (OR 95% CI) for maternal characteristics or neonatal outcomes.

Among 17,177 pregnant women, different types of hypertension present varying risks for both the mother and fetus. There is an increased risk of cesarean section in patients with preeclampsia (OR 2.04, 95% CI: 1.43-2.88). For the newborn, a higher risk of preterm birth is associated with maternal chronic hypertension (OR 3.09, 95% CI: 1.91-4.83) and preeclampsia (OR 5.07, 95% CI: 3.28-7.65). Additionally, there is a higher risk of low birth weight in cases of maternal chronic hypertension (OR 3.2, 95% CI: 2.04-4.88), preeclampsia (OR 5.07, 95% CI: 3.34-7.52), and gestational hypertension (OR 2.72, 95% CI: 1.49-4.68). Furthermore, only newborns of patients with preeclampsia had a higher risk of an Apgar score lower than 7 in the first minute (OR 2.95, 95% CI: 1.45-5.38).

In the study population adjusted for body weight, the different types of hypertension represent different risks in the mother and foetus. These complications were mostly associated with preeclampsia.