Association between gestational age at delivery beyond 37 weeks and perinatal outcomes in gestational hypertension.

To evaluate the association between gestational age at delivery beyond 37 weeks and perinatal outcomes in women initially diagnosed with gestational hypertension(GH). This retrospective cohort study was conducted involving 661 singleton pregnancies admitted with a diagnosis of gestational hypertension who delivered at or beyond 37 weeks of gestation. Participants were grouped according to the gestational week of delivery (37-37+6, 38-38+6, 39-39+6, and ≥ 40 weeks). Composite maternal and neonatal outcomes were evaluated using multivariable logistic regression. After adjusting for confounders, delivery at 39-39+6 weeks was associated with a lower risk of composite neonatal outcomes (aOR = 0.53, 95%CI: 0.29-0.98) without increasing the risk of composite adverse maternal outcomes (aOR = 1.36, 95%CI: 0.78-2.35). This association remained consistent in a sensitivity analysis excluding women who progressed to preeclampsia (aOR 0.49, 95% CI 0.26-0.95). In contrast, the 37-37+6 weeks group demonstrated the highest risk of adverse composite neonatal outcomes (26.53%) and some adverse maternal outcome (preeclampsia:23.47%, placental abruption:2.04%). Delivery at ≥40 weeks was associated with an increased risk of intrapartum cesarean section (aOR = 2.78, 95% CI: 1.28-6.05). Among women initially diagnosed with gestational hypertension who remained clinically stable beyond 37 weeks, delivery at 39-39⁺⁶ weeks was associated with more favorable neonatal outcomes without an apparent increase in maternal morbidity. However, given the observational design and potential confounding by clinical indication, these findings should be interpreted as associative rather than causal, and individualized management remains essential.