vaginal deliveries in a modern academic practice Haitham Baghlaf, Matthew Goldshore, Nancy Hueppchen, Jessica Bienstock, Erika Werner The Johns Hopkins University School of Medicine, Gynecology and Obstetrics, Baltimore, MD, The Johns Hopkins University School of Public Health, Population, Family and Reproductive Health, Baltimore, MD OBJECTIVE: The rate of forceps assisted vaginal deliveries has consistently decreased over the past two decades as has forceps training in residency programs. Given this curricular change, we sought to estimate the rate of delivery complications associated with forceps in a contemporary academic practice. STUDY DESIGN: We performed a case-control study at a teaching hospital between 2005 and 2011 of operative deliveries involving residents for singleton cephalic neonates. The outcomes of interest included neonatal abrasion/laceration, brachial plexus injury, cephalohematoma, facial nerve injury, fracture, intracranial hemorrhage, seizure, neonatal transfusion and severe maternal perineal laceration defined as a third or fourth degree laceration. The rates of these complications when forceps were used were compared to the rates when vacuums were used. All pregnancies complicated by congenital anomalies and those delivered before 34 weeks were excluded. RESULTS: A total of 331 FAVDs occurred, comprising 3.2% of the total singleton, cephalic deliveries occurring after 34 weeks. Compared to vacuums, forceps were associated with no significant difference in any neonatal complications except facial nerve injury (Table). When maternal complications were examined, forceps were associated with significantly more severe perineal lacerations compared to vacuum (OR 4.42; 95% CI 3.136.26). After adjusting for gestational age, birthweight, parity, anesthesia and indication, facial nerve injury and severe perineal laceration continued to be the only complications more associated with forceps. While our study may be underpowered to identify some neonatal complication differences, the rate of cephalohematoma, fractures and seizures were greater with vacuum than with forceps. CONCLUSION: In an academic setting, forceps continue to be a relatively safe alternative compared to vacuums with regard to the neonate, but forceps are associated with significantly higher odds of severe perineal lacerations. 797 Successful trial of labor after cesarean: influence of fetal growth Ibrahim Hammad, Hind Beydoun, Cande Ananth, Suneet Chauhan Eastern Virginia Medical School, Department of Obstetrics and Gynecology, Norfolk, VA, Eastern Virginia Medical School, Department of Public Health, Norfolk, VA, Columbia University Medical Center, Department of Obstetrics and Gynecology, New York, NY, Eastern Virginia Medical School, Department of Obstetrics and Gynecology, Norfolk, VA OBJECTIVE: To determine the extent to which fetal growth influences the success of trial of labor after cesarean (TOLAC). STUDY DESIGN: This is a secondary analysis of MFMU cesarean delivery registry, restricted to women with at least 1 prior cesarean delivery and who delivered a non-anomalous singleton at term (37 weeks or more). Fetal growth was assessed based on birthweight percentiles categorized as 5, 5-9, 10-19, 20-29, 30-79, 80-89, 90-95, 95 for gestational age. Risk ratios for successful TOLAC in relation to fetal growth centiles (30-79% as the reference) were derived from log-linear regression models following adjustment for maternal age, ethnicity, education, cigarette smoking and marital status. RESULTS: Of the 14,958 TOLAC that met the inclusion criteria, 74% were successful. The success rate of TOLAC was strongly dependent on fetal growth, ranging from 81% for newborns at 5-9% to 57% for newborns at 95% (Figure). The analysis indicates that compared to newborns with fetal growth centiles at 30-79%, the probability of success of TOLAC is higher for those at 10-29% percentiles and lower for those at 80% or higher. CONCLUSION: The success of TOLAC is heavily influenced by fetal growth. While these findings await corroboration in other large cohorts, fetal growth should be considered an important factor in physician attempts to determine appropriate candidates to ensure successful TOLAC. Adjusted ORs for PRC according to gestational age at delivery in Hispanics*