Background: In Sweden, the frequency of cesarean section of the second twin after vaginal birth of the first twin has increased in recent years. Methods: To investigate the indications for second twin cesarean sections, all twin deliveries at Huddinge University Hospital from 1995 to 1997 were reviewed retrospectively. The rates of cesarean section for the second twin were compared with figures from the whole country, based on the Swedish medical birth register. Results: Thirty-one percent of all twin deliveries had a spontaneous onset and spontaneous vaginal delivery. The total twin cesarean section rate, including cesarean section for the second twin, was 45% at Huddinge University Hospital in 1995–1997 and 44% in Sweden in 1995. Cesarean section for the second twin after vaginal delivery of the first twin occurred in 11%. On review, 2/3 of the cesarean sections for the second twin were considered potentially avoidable. Conclusion: In normal twin pregnancies with vertex/nonvertex presentation, the favorable fetal outcome and also the maternal risks associated with cesarean section support vaginal delivery as the recommended delivery route. Extraction or version of a second nonvertex twin should be attempted before cesarean section for this twin is performed.