Vaginal delivery for the selected frank breech infant at term.

A retrospective analysis of 254 term breech deliveries was done, with term breech presentations managed by a protocol in which cesarean section was done for nonfrank breech presentation, or estimated fetal weight in excess of 4000 g. Patients with frank breech presentation were assigned to one of three groups based on x-ray pelvimetry and estimated fetal weight. Of 70 group 1 patients (adequate pelvis with estimated fetal weight less than 3600 g), 79% had a vaginal delivery. Of 21 group 2 patients (borderline pelvis or estimated fetal weight of 3600 to 4000 g), 67% delivered vaginally. In group 3 (contracted pelvis or estimated fetal weight greater than 4000 g), all patients were delivered by cesarean section. The overall cesarean section rate for frank breech infants was 36%. Apgar scores were not significantly different for infants delivered vaginally or abdominally. The crude perinatal mortality rate was 11.8; the corrected perinatal mortality rate was 0. These findings further substantiate the safety of these criteria in management of term breech presentations.