[Estrogen role in the luteal phase support in in vitro fertilization with embryo transfer cycles].

Objective: To evaluate the effectiveness of estradiol administration for luteal phase support and to describe the progesterone and estradiol behavior in vitro fertilization-embryo transfer luteal phase.

Material And Methods: Patients undergoing in vitro fertilization-embryo transfer with controlled ovarian hyperstimulation and using gonadotropin releasing hormone agonist. They were divided at random into two groups: group 1 would receive progesterone alone, and group 2 would take estrogen and progesterone. Serum concentrations of estradiol and progesterone were measured on days 7 and 14 post-embryo transfer.

Results: We examined 52 patients; 24 received progesterone alone and 28 took estrogen and progesterone. Significantly higher estradiol and progesterone concentrations on day 14 were found in pregnant women. It was not on day 7. A significant increment of estrogen was found in the estrogen and progesterone group. Progesterone did not increase significantly. Pregnancy rate was the same in both groups.

Conclusions: For patients undergoing in vitro fertilization-embryo transfer, the addition of estradiol to the progesterone support regimen does not have beneficial effects in terms of pregnancy rate. On day 7 neither progesterone nor estradiol are good predictors of pregnancy.