To study the clinical characteristics and maternal and perinatal outcomes of single pregnancy with preeclampsia superimposed chronic hypertension and non-chronic hypertension in single pregnancy.

A retrospective analysis was performed on the singleton pregnancies with gestation≥20 weeks diagnosed as preeclampsia, who were admitted to The Third Affiliated Hospital of Guangzhou Medical University during 1 January 2009 and 31 December 2017.All the eligible patients were divided into preeclampsia superimposed chronic hypertension group and preeclampsia with non-chronic hypertension group.The clinical characteristics and maternal and perinatal outcomes of the two groups were analyzed.

Among 2361 pregnant women with preeclamps, there were 75 cases (27.08%) in the chronic hypertension group and 2286 cases (72.92%) in the non-chronic hypertension group. The mean age of pregnant women in the preeclampsia superimposed chronic hypertension group was significantly higher than that in the non-chronic hypertension group. In the preeclampsia superimposed chronic hypertension group, the incidence of advanced maternal age women, multiparas, scarred uterus, admission to hospital were outpatient, unregular or no prenatal care, maternal referral to ICU, preterm labor, abortion, and stillbirth were higher. The gestational age at delivery and neonatal weight were both lower than that in preeclampsia superimposed chronic hypertension group, with statistically significant differences (all P<0.05).

The mean age of pregnant women in the preeclampsia superimposed chronic hypertension group was significantly higher than that in the preeclampsia group, with the increasing risk of maternal and neonatal adverse outcomes. Therefore, attentions should be paid to pregnant women with chronic hypertension. To reduce the adverse outcomes of maternal and perinatal, management of high-risk pregnancy should be strengthened, and early diagnosis and treatment should be standardized.