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Objective To determine the difference in the rates of severe perineal lacerations between forceps-assisted vaginal deliveries in the occiput-posterior (OP) position compared with forceps-assisted vaginal deliveries in which the fetal head was rotated to occiput anterior (OA) prior to delivery. Methods We studied a retrospective cohort of 148 women who had a forceps-assisted vaginal delivery from 2008–2011 at the University of Pittsburgh. Mild perineal lacerations were defined as first or second degree, and severe lacerations were defined as third or fourth degree. Chi-square and t tests were used for bivariate and logistic regression was used for multivariable analyses. P<.05 was considered statistically significant. Results Of 148 forceps-assisted deliveries, 81 delivered OA after either manual or forceps rotation, 10 delivered in the OP or occiput-transverse position after an unsuccessful rotation, and 57 delivered OP without attempted rotation. No significant differences were found between demographic, obstetric and neonatal characteristics of the groups. Overall, 86 (67.7%) women had mild lacerations and 41 (32.3%) had severe lacerations. A significantly greater rate of severe perineal lacerations were found in the OP nonrotated compared with the rotated group (43.4% compared with 24.3%; P=.02). In multivariable analyses, adjusted for age, race, insurance, body mass index, gestational age, parity, episiotomy and neonatal weight, forceps-assisted vaginal delivery in the OP position without rotation remained significantly more likely to be associated with severe lacerations (OR 3.67; 95% CI 1.42–9.47). Conclusion Forceps-assisted vaginal delivery after rotation of an OP position to an OA position is associated with less severe maternal perineal trauma than forceps-assisted delivery in the OP position.