ObjectiveTo explore the predictors of seizures during pregnancy, and to explore whether seizure control in the 6 months and 1 year prior to pregnancy can predict the risk of seizures during pregnancy and the occurrence of adverse maternal and infant outcomes, so as to guide the choice of the best fertility timing for women with epilepsy (WWE).MethodsA total of 46 WWE with 48 pregnancies were enrolled in Epilepsy Clinics of Tianjin Medical University from August 2016 to January 2020. Retrospective analysis was used to analyze the risk factors of epileptic seizures in pregnancy. The patients were grouped according to the time of absence of seizures during pregnancy. To analyze the influence of epileptic seizure, pregnancy complications and pregnancy outcome.Results Among 48 pregnancies, the risk of premature rupture of membranes was significantly higher in patients with epilepsy than those without epilepsy (34.6% vs. 0.0%), and the difference was statistically significant (P<0.01). There was no significant difference in the risk of PIH, GDM, gestational anemia and pregnancy complications (P>0.05). For women who had seizure during pregnancy, the mean birth weight of the offspring was slightly lower, and the incidence of low birth weight and fetal distress was higher, but the difference was not statistically significant (P>0.05); Seizures in the 6 months before pregnancy were significantly associated with seizures during pregnancy [RR=4.28, 95%CI (2.10, 8.74), P<0.01]. Further, the risk of adverse pregnancy outcomes increased significantly [RR=2.00, 95%CI (1.10, 3.65), P<0.05] for WWE who had seizure in 6 month before pregnancy; The rates of seizures during pregnancy in the two groups were 25.0% and 20.0%, but the difference was not statistically significant (P>0.05). Compared with the 6-months, the ≥1 year group had a lower risk of PIH and gestational anemia, and the offspring had a lower risk of low birth weight, premature delivery and fetal distress, but the difference was not statistically significant (P>0.05).ConclusionEnsuring seizure-free at least 6 months before pregnancy will significantly reduce the probability of seizures during pregnancy, and is significantly associated with a lower incidence of adverse pregnancy outcomes. Women of childbearing age with epilepsy are advised to plan pregnancy after reaching seizure-free at least 6 months.