In this observational study, we investigated the maternal and perinatal complications of caesarean delivery performed in the second stage compared with the first stage of labour at a tertiary hospital in I stanbul. This study was performed from June 2008 to July 2011. Primary maternal outcomes measured included intraoperative surgical complications, surgery duration, need for blood transfusion, endometritis, requirement for hysterectomy, unintended extension and length of hospital stay. Neonatal outcomes included a 5 min Apgar score <= 3, admission to a neonatal intensive care unit, fetal injury, septicaemia and neonatal death. In total, 3,817 caesarean deliveries were available for analysis; 3,519 were performed in the first stage, and 298 in the second stage. Caesarean deliveries performed in the second stage were associated with increased intraoperative complications, unintended extensions, need for blood transfusion, higher rates of endometritis and requirement for hysterectomy and were, therefore, associated with longer operation time and hospital stay. Neonatal complications included a significantly low Apgar score at 5 min, increased neonatal death, admission to the neonatal intensive care unit, septicaemia and fetal injury (all p < 0.05). Caesarean deliveries performed in the second stage of labour were associated with higher rates of maternal and neonatal complications, particularly in women who had undergone previous caesarean delivery.