Vaginal trial outcomes and emergency cesarean section factors among women with different classifications of hypertensive disorders of pregnancy

Background: Hypertensive disorders of pregnancy (HDP) are a prevalent complication and a leading cause of maternal and perinatal mortality. While vaginal delivery is generally possible for most women with HDP, there is no standardized framework detailing variations in vaginal delivery outcomes across different HDP classifications or identifying the factors influencing emergency cesarean section (EmCS).Objective: To explore the vaginal trial outcomes and risk factors associated with emergency cesarean section among women with different classifications of HDP.Methods: This was a single-center retrospective cohort study of 894 pregnant women with HDP who underwent a vaginal trial. Of these, 584 were diagnosed with gestational hypertension, 216 with pre-eclampsia, and 94 with chronic hypertension. The study collected and compared detailed maternal and perinatal outcomes.Results: (1) The success rate of vaginal delivery ranged from 85.1% to 90.8% across various classifications of HDP without significant differences. (2) Chronic hypertension was four times more likely to lead to intrapartum poorly controlled blood pressure than gestational hypertension. (3) Factors influencing EmCS in HDP included parity, antepartum BMI, labor induction, intrapartum fever, intrapartum antihypertensive use, and oxytocin during stages of labor. Parity served as an independent protective factor across all HDP classifications. Stratified analysis revealed that for gestational hypertension, risk factors included antepartum BMI ≥ 30 kg/m2, labor induction, and intrapartum antihypertensive use. For pre-eclampsia, oxytocin and intrapartum fever were risk factors. In chronic hypertension, antepartum BMI ≥ 30 kg/m2 and intrapartum fever were identified as risk factors, although the former was not significant.Conclusion: The success rate of vaginal trials across various classifications of HDP is high. Vaginal trial can impact intrapartum blood pressure, particularly for women with chronic hypertension. Tailored management strategies should include encouraging vaginal trial for multiparous women, control of antepartum BMI, judicious use of labor induction, and vigilant monitoring of hypertension and fever, with individualized evaluation and treatment based on HDP classification.