Ten women underwent obstetric hysterectomy at St George's Hospital, London between 1992 and 1998, with an apparent seven-fold increase in incidence in recent years. All hysterectomies were performed as emergency procedures, with massive postpartum haemorrhage being the major indication for operation in nine cases. Abnormal placentation was the single commonest cause, seven cases being associated with previous caesarean section. There were no maternal or fetal mortalities, but major surgical complications, including urinary tract and vascular injury occurred in one case. In view of the increasing risk of obstetric hysterectomy following previous caesarean section, high risk cases associated with abnormal placentation may be identified using ultrasound, allowing appropriate pre-operative counselling regarding the risk of peripartum hysterectomy.