Comparison of Kidney Function between Gestational Hypertension and Preeclampsia

Although gestational hypertension (GH) is thought to be different from preeclampsia (PE), in Japan GH and PE are usually treated as the same disease (i.e., pregnancy-induced hypertension). Here we sought to determine whether there are any differences in fetal growth and maternal kidney function between pregnancies with PE and those with GH. We retrospectively analyzed 61 GH patients and 60 PE patients with singleton pregnancies who delivered at Okayama University Hospital (2008-2015). We compared maternal and perinatal outcomes and maternal kidney function parameters between the GH and PE pregnancies. The mean values of maternal age (p=0.01), gestational age at delivery (p<0.0001), placental weight (p=0.002), birth weight and height (p<0.0001, p=0.0001), and head circumference standard deviation score (p=0.007) of newborns of the GH group were significantly higher than those of the PE group. The duration until termination of PE or GH was not significantly correlated with kidney function. The birth weight percentile was significantly correlated with kidney function in PE but not GH. However, GH patients with poor kidney function and small-for-gestational age infants showed perinatal outcomes similar to those of the PE group. Monitoring kidney function is thus important for determining the severity of PE and GH.