Assessment of the follicular cortisol:cortisone ratio

Cortisol and cortisone concentrations in serum and follicular fluid (FF) from women undergoing in-vitro fertilization (IVF) treatment were monitored. Four groups were included: group 1, women in their natural menstrual cycle having an endogenous mid-cycle surge of gonadotrophins; group 2, women in their natural menstrual cycle receiving human chorionic gonadotrophin (HCG) for ovulation induction; group 3, women receiving exogenous gonadotrophins for ovarian stimulation and HCG for ovulation induction; and group 4, women receiving exogenous gonadotrophins for ovarian stimulation, follicles being aspirated immediately before administration of HCG. In this study, 12 follicles contained oocytes which resulted in clinical pregnancy after IVF. Cortisone concentrations were significantly higher in FF compared with that of matched serum samples, while the opposite was observed for cortisol, resulting in cortisol:cortisone ratios being significantly lower in FF compared with serum. FF from group 4 showed significantly higher cortisone concentrations than FF from each of the other three groups. FF from group 1 showed significantly higher cortisone concentrations and significantly lower cortisol:cortisone ratios in comparison with groups 2 and 3. None of the observed parameters pinpointed any of the follicles containing oocytes which resulted in a clinical pregnancy. The intrafollicular concentrations of cortisol and cortisone suggest that pre-ovulatory follicles actively convert cortisol to cortisone. Neither FF concentrations of cortisol and cortisone nor the cortisol:cortisone ratio seem to reflect implantation potential of the derived pre-embryos.