[Estrogen role in the luteal phase support in in vitro fertilization with embryo transfer cycles]. / Papel de los estrógenos en el soporte de la fase lútea en ciclos de fertilización in vitro con transferencia de embriones.

ABSTRACT

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.