Delaying the initiation of progesterone supplementation until the day of fertilization does not compromise cycle outcome in patients receiving donated oocytes: a randomized study

ObjectiveTo determine whether the initiation of P supplementation as artificial luteal phase support (day −1, day 0, or day +1 of egg donation) in extensive programs of ovum donation influences cycle cancellation, pregnancy outcome, and implantation rate in day 3 embryo transfers.DesignProspective randomized trial.SettingOocyte donation program at the Instituto Valenciano de Infertilidad, Valencia, Spain.Patient(s)Three hundred recipients with normal ovarian function, absence of uterine anomalies, and undergoing their first egg donation were recruited between September 2003 and September 2004.Intervention(s)A computer-based randomization divided the recipients into three groups when hCG was administered to their matched donors. The first group (group A) started P supplementation the day before oocyte retrieval; the second group (group B) started P supplementation on the day of the oocyte retrieval; and the third group (group C) started P supplementation 1 day after the egg retrieval once fertilization was confirmed.Main Outcome Measure(s)Implantation, pregnancy, and ongoing pregnancy rates were the primary outcome measures considered. The secondary outcome measure was the cancellation rate, especially due to fertilization failure.Result(s)Global cancellation rate and cancellation rate due to fertilization failure were significantly higher in group A (12.4% and 8.2%, respectively) than in group C (3.3% and 0%, respectively). Reproductive outcome was similar in all the groups except for a higher biochemical pregnancy rate in group A (12.9%) than in groups B (6.6%) and C (2.3%).Conclusion(s)Initiation of P on day +1 of embryo development decreases cancellation rates of day 3 embryo transfers in extensive programs of ovum donation without any deleterious effect on pregnancy outcome or implantation rate.