Number of follicles, oocytes and embryos in human in vitro fertilization is relative to serum estradiol and progesterone patterns during different types of ovarian hyperstimulation.

Preovulatory serum estradiol and progesterone levels as well as their ratio were compared in different types of ovulation induction in order to determine whether these findings could be used to predict the number of preovulatory follicles, number of oocytes aspirated and embryos obtained. Significantly more oocytes were retrieved by follicular aspiration and significantly more embryos developed in patients receiving gonadotropin-releasing hormone agonist and human menopausal gonadotropins than in those given other ovulation inductors. On days -2 and -1 of the cycle, serum estradiol levels were significantly lower in pure follicle-stimulating hormone induction. Serum progesterone was significantly higher in pure follicle-stimulating hormone cycles on days -4 and -3. In clomiphene citrate and human menopausal gonadotropin induction, progesterone levels were significantly lower on days -2 and -1, and on the day of follicular aspiration. Ratios of estradiol/progesterone were lower in pure follicle-stimulating hormone group from day -3 to day -1 of the cycle. A significant correlation was found between estradiol and progesterone serum levels and the numbers of preovulatory follicles, oocytes and embryos. The study revealed the usefulness of serum estradiol and progesterone determinations in assisted reproduction.