From 1962 to 1966, external cephalic version, with the patient under anesthesia, was performed after 34 weeks gestation in 500 patients, and the deliveries over this period were 38,831. Successful version was achieved in approximately 50%. The perinatal mortality attributable to the procedure was 1.6%, and after correction for gross fetal abnormality, the subsequent perinatal mortality after successful version was 0.4% and after failed version 1.8%. The cesarean section rate after successful version was 12%, and that after failed version was 22%. The risk of this procedure should be compared with the overall risk of breech delivery, and the incidence of cesarean section with breech presentation. Except where breech mortality is between 1% and 2%, version with anesthesia is justifiable to reduce the incidence of the malpresentation with its attendant hazards. The procedure will also reduce the cesarean section rate.
Bonnar J, Howie PW, MacLennan SH. External Cephalic Version With Anesthesia. JAMA. 1968;205(2):97-101. doi:10.1001/jama.1968.03140280051013