Risk factors for adverse maternal‑neonatal outcomes in pregnant women with epilepsy and the impact of different anti-seizure medications exposures on neonatal birth weight.

OBJECTIVE: To investigate the risk factors for adverse maternal‑neonatal outcomes in pregnant women with epilepsy and to analyze the effects of different anti-seizure medications (ASMs) on neonatal birth weight, thereby providing clinical evidence for the management of epilepsy during pregnancy. METHODS: A total of 218 pregnant women with epilepsy who delivered at our hospital between January 2021 and December 2025 were enrolled. Demographic data, epilepsy‑related clinical characteristics, ASM regimens, pregnancy complications, and maternal‑neonatal outcomes were collected. Patients were divided into an adverse outcome group (n = 74) and a favorable outcome group (n = 144) based on the occurrence of adverse maternal‑neonatal outcomes (including preterm birth, low birth weight, fetal distress, and neonatal malformations). Logistic regression analysis was performed to identify independent risk factors for adverse outcomes. Among patients receiving monotherapy (n = 131, 60.09%), they were categorized into lamotrigine, levetiracetam, carbamazepine, oxcarbazepine, and valproate groups according to ASM exposure during pregnancy; a separate polytherapy group (n = 87, 39.91%) was also included. Analysis of variance (ANOVA) was used to compare neonatal birth weight across groups. RESULTS: Multivariate logistic regression showed that uncontrolled epilepsy before and during pregnancy (presence of seizures within six months before pregnancy: OR=4.300, P < 0.001; any seizure during pregnancy: OR=3.661, P < 0.001; increased seizure frequency during pregnancy: OR=3.781, P < 0.001), focal epilepsy (OR=2.245, P = 0.005), polytherapy (OR=2.046, P = 0.014), and gestational hypertension (OR=2.764, P = 0.008) were independent risk factors for adverse maternal‑neonatal outcomes. Regarding neonatal birth weight, the monotherapy group had a significantly higher mean birth weight (3170 ± 452 g) than the polytherapy group (2963 ± 501 g, P = 0.002). Among monotherapy regimens, the valproate group had the lowest mean birth weight (2805.50 ± 395.53 g), which was significantly lower than that of the lamotrigine group (3273.51 ± 429.49 g, P = 0.012) and the levetiracetam group (3236.51 ± 407.47 g, P = 0.023). No significant differences were observed among the lamotrigine, levetiracetam, carbamazepine, and oxcarbazepine groups (ANOVA: F=3.822, P = 0.006). CONCLUSION: Uncontrolled epilepsy before and during pregnancy, polytherapy, focal epilepsy, and gestational hypertension are independent risk factors for adverse maternal‑neonatal outcomes in pregnant women with epilepsy. Different ASMs have differential effects on neonatal birth weight; valproate and polytherapy are associated with significantly lower birth weight. Physicians should counsel women with epilepsy that achieving at least six months of seizure freedom before conception is associated with improved maternal-neonatal outcomes. Lamotrigine or levetiracetam monotherapy should be prioritized whenever possible, and close monitoring should be maintained throughout pregnancy.