The concentration of inhibin B in follicular fluid: relation to oocyte maturation and embryo development

BACKGROUND: The objective of the present study was to investigate the correlation between inhibin B and estradiol levels in follicular fluid (FF) with the quality of subsequent embryo development from in-vitro fertilized oocytes aspirated from the same follicle. METHODS: A total of 156 infertile women undergoing controlled ovarian stimulation for IVF and embryo transfer was recruited to the present study. Prospectively, 233 FF samples and matched mature oocytes were studied. Concentrations of inhibin B and estradiol were determined by enzyme-linked immunosorbent assay (ELISA) and immunofluorometric assay (IFMA) respectively. RESULTS: Inhibin B levels in FF were significantly correlated with embryo scores on days 2 and 3 (48 and 72 h after oocyte retrieval). In contrast, both inhibin B and estradiol levels in FF were inversely related to age. Furthermore, FF inhibin B levels were inversely associated with serum FSH levels on day 3 of the menstrual cycle, which was believed to reflect the ovarian reserve. CONCLUSION: Inhibin B in FF may serve as an effective marker of follicular development and a useful predictor of quality of embryo. In addition, quality of oocyte is age-related and declines as age increases.