SUCCESSFUL FERTILISATION OF HUMAN OOCYTES IN VITRO: CONCENTRATION OF ESTRADIOL-17S, PROGESTERONE AND ANDROSTENEDIONE IN THE ANTRAL FLUID OF DONOR FOLLICLES.11

Abstract

Oocytes and matched samples of follicular fluid were obtained from 156 pre-ovulatory follicles in 125 women 26-36 h after either administration of hCG or the onset of an endogenous LH surge. Concentrations of estradiol- 17β (E₂), progesterone (P) and androstenedione (A₄) in the fuid of individual donor follicles were measured and related to the success of fertilisation of oocytes in vitro and the incidence of pregnancies after embryo transfer. Oocytes which gave rise to successful pregnancies were obtained from follicles which contained greater concentrations of E₂ and a higher ratio of E₂ :P than did oocytes from which pregnancy did not result. These data provide direct evidence in support of the hypothesis that estrogenic follicles are the sole source of ova which undergo fertilisation and subsequently give rise to pregnancy in women.