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

OBJECTIVE

To 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.

DESIGN

Prospective randomized trial.

SETTING

Oocyte 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.