A Canadian team has achieved high maturation and pregnancy rates by using eggs matured in vitro with a group of 40 women undergoing in vitro fertilisation (IVF). The group, from McGill University and the Royal Victoria Hospital in Montreal, reported that from 45 cycles of the new procedure, 15 clinical pregnancies have so far been approved. Five women have delivered seven healthy babies, four have miscarried and six are still pregnant, resulting in an overall success rate of 33 per cent. In the initial trial of the technique, 25 IVF cycles were carried out in 20 women with an average age of 36 years. Two of the patients achieved clinical pregnancies with two successful deliveries, giving a success rate of 40 per cent.

Patients participating in this programme were treated in a natural menstrual cycle with just one injection of the common fertility drug Profasi (chorionic gonadrotrophin) before immature eggs were removed - usually between days 10 and 14 of the menstrual cycle. They were then matured for 24-48 hours without freezing and then fertilised as normal.