OBJECTIVE: To compare maternal and neonatal outcomes after preterm prelabor rupture of membranes (PROM) from 23 to 34 weeks of gestation in twin compared with singleton gestations. METHODS: We conducted a secondary analysis of an obstetric cohort of 115,502 individuals and their singleton or twin neonates born in 25 hospitals nationwide (2008-2011). Those with preterm PROM from 23 0/7 through 33 6/7 weeks of gestation were included; neonates with major fetal anomalies were excluded. The coprimary outcomes for this analysis were composite maternal morbidity (chorioamnionitis, blood transfusion, postpartum endometritis, wound infection, sepsis, venous thromboembolism, intensive care unit admission, or death) and composite major neonatal morbidity (persistent pulmonary hypertension, intraventricular hemorrhage grade III or IV, seizures, hypoxic-ischemic encephalopathy, necrotizing enterocolitis stage II or III, bronchopulmonary dysplasia, stillbirth subsequent to admission, or neonatal death before discharge). Logistic regression was used to estimate unadjusted and adjusted odds ratios (ORs) with 95% CIs for twin compared with singleton gestations. RESULTS: Of 1,531 (1.3%) individuals who met eligibility criteria for this analysis, 218 (14.2%) had twin gestations. The median gestational age at preterm PROM was similar between those with twins and singletons (31.2 weeks [interquartile range 27.4-32.9] vs 30.6 weeks [interquartile range 26.9-32.7], P=.23); however, those with twin gestations had a shorter median latency period (2.0 days [interquartile range 1.0-5.0] vs 3.0 days [interquartile range 2.0-8.0], P<.001). After adjustment for potential confounders, odds of experiencing composite maternal morbidity (17.9% vs 19.3%, adjusted OR 0.97, 95% CI 0.66-1.42) or composite neonatal morbidity (20.4% vs 20.5%, OR 0.97, 95% CI 0.72-1.31) did not differ between groups. CONCLUSION: In a large, diverse cohort, the likelihood of composite maternal or neonatal morbidity per fetus after preterm PROM was similar for twin and singleton gestations.