Serial haemodynamic investigations were performed in 15 women delivered by elective caesarean section under epidural anaesthesia at 38-40 weeks gestation. Cardiac output was measured by Doppler and cross-sectional echocardiography at the aortic valve. No haemodynamic changes were demonstrable after attainment of surgical anaesthesia (T5 or above). Stroke volume increased 13% after delivery of the placenta and remained elevated until the end of the operation at which time cardiac output was 11% above pre-operative values. Stroke volume and cardiac output fell during the first postoperative day. Heart rate remained elevated at pre-operative values for 48 h after delivery. There was a fall in heart rate and cardiac output between the second and the sixth days after delivery. By 2 weeks after delivery cardiac output was 28% lower than pre-operative values. Compared with pre-operative values, diastolic blood pressure was lower on the first and second postnatal days.