Relationship between the steroid and prolactin concentration in follicular fluid and the maturation and fertilizaton of human oocytes

Abstract

Seventyeight follicles and their follicular fluid were aspirated from 46 women undergoing in vitro fertilization (IVF) procedures after stimulation of the ovaries with a low-dose human menopausal gonadotropin/human chorionic gonadotropin stimulation regimen. The concentrations of estradiol (E₂), progesterone (P), testosterone (T), and prolactin (PRL) were measured in follicular fluid and related to the maturation of the oocyte-corona-cumulus complex (OCCC) and the fertilization of oocytes. Follicles containing mature oocytes had significantly higher follicular fluid E₂ and P levels than follicles with intermediate and immature oocytes. A constant decrease in PRL and T values with advancing follicular maturation was observed. Similar results were obtained when the fertilizing ability of the oocytes was examined. The gradual decline in follicular fluid PRL and T levels during follicular development was connected with increasing E₂ and P biosynthesis and therefore seems to be an important precondition for normal follicular and oocyte maturation.