To evaluate the quality of intra-operative anaesthesia and recovery characteristics of two different anaesthesia regimens, 60 healthy women undergoing ultrasound guided oocyte retrieval for in vitro fertilization procedures were randomly allocated to receive either a propofol/fentanyl or a midazolam/remifentanil based anaesthesia. The surgical procedure was successful in all patients and no severe side effects were reported by any patient. Four patients in the midazolam/remifentanil group (13%) would not accept the same anaesthetic procedure for further in vitro fertilization treatment due to intra-operative awareness, while all propofol/fentanyl patients were prepared to accept the same procedure again (P < 0.05). Patients in the propofol/fentanyl group required manual ventilation more frequently through a facemask than those patients treated with the midazolam/remifentanil combination (50% and 30%, respectively; P < 0.05). The time to achieve an Aldrete's score of 10 was shorter in the midazolam/remifentanil patients (2 +/- 2 min) than in those who received propofol/fentanyl (4 +/- 2 min) (P < 0.001), but no differences were observed in the time required to be 'fit to discharge' from the post-anaesthesia care unit. We conclude that the use of a midazolam/remifentanil regimen is as effective and safe as a fentanyl/propofol regimen in patients undergoing transvaginal oocyte retrieval for in vitro fertilization procedures.