OBJECTIVE: To explore the relevant factors associated with successful labor in twin pregnancies and investigate maternal and fetal outcomes in the group with failed labor. METHODS: A retrospective analysis was conducted on twin pregnancies that underwent labor in our hospital from July 2016 to June 2023. A total of 519 cases were divided into two groups: the successful labor group (450 cases with vaginal delivery of both fetuses) and the failed labor group (69 cases with cesarean delivery of one or two fetuses). The relevant factors of the labor, as well as the maternal and fetal outcomes, were analyzed between these two groups. RESULTS: Multivariate analysis indicated that advanced maternal age (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.05-1.22), high pre-delivery body mass index (OR 1.11, 95% CI 1.04-1.19), and vertex/transverse twins (OR 3.75, 95% CI 1.35-10.40) were risk factors for the failure of vaginal labor. Multiparity (OR 0.15, 95% CI 0.08-0.29), premature birth (OR 0.43, 95% CI 0.24-0.78), and neuraxial analgesia (OR 0.37, 95% CI 0.20-0.72) were protective factors for the failure of delivery. There were no statistically significant differences (P >
0.05) in decreased hemoglobin and neonatal outcomes between the two groups. The postpartum hospitalization time in the successful labor group was shorter than that in the failed labor group (P <
0.05). CONCLUSIONS: Labor in twin pregnancies is generally safe. Factors such as multiparity, previous premature birth, and neuraxial analgesia can significantly enhance the likelihood of a successful vaginal delivery.