101. Interactions between serum FSH, inhibin B and antral follicle count in the decline of serum AMH during the menstrual cycle in late reproductive age.
- Author
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Robertson DM, Lee CH, and Baerwald A
- Subjects
- Adolescent, Adult, Female, Healthy Volunteers, Humans, Middle Aged, Young Adult, Aging blood, Aging pathology, Anti-Mullerian Hormone blood, Cell Count, Follicle Stimulating Hormone blood, Inhibins blood, Menopause blood, Menstrual Cycle blood, Ovarian Follicle cytology, Ovarian Follicle pathology
- Abstract
Objective: To investigate the hormonal interrelationships during the menstrual cycle in women of late reproductive age with suppressed serum AMH and antral follicle count (AFC)., Methods: Serum hormones (AMH, FSH, LH, estradiol, progesterone, inhibin A, inhibin B), AFC (2-10 mm) and AMH/AFC ratio (an estimate of AMH/follicle) were assessed every 2-3 days across the menstrual cycle in 26 healthy ovulatory women aged 18-50 years., Results: An 11-fold fall in AMH/AFC was observed in women aged ≥45 years compared to those 18-45 years ( P < .001). Although women ≥45 years exhibited normal menstrual cycle patterns of serum estradiol, progesterone, LH and inhibin A, FSH was elevated ( P < .001) and inhibin B suppressed ( P < .001) compared to the younger group. Overall FSH was inversely correlated ( r = .55, P < .05) and AMH directly correlated ( r = .88, P < .01) with AFC; however, these relationships were curvilinear and more pronounced when AFC was low. Inhibin B was directly linearly correlated ( r = .70, P < .01) with AFC across both high and low AMH/follicle groups., Conclusions: It is hypothesized that the marked fall in AMH/follicle in late reproductive age is attributed to the change in the hormonal interplay between the pituitary and ovary. The fall in AFC leads to a decrease in inhibin B and a concomitant increase in FSH by a recognized feedback mechanism. It is postulated the elevated FSH suppresses AMH either directly or indirectly through oocyte-specific growth factors leading to a marked fall in AMH/follicle. We propose that pituitary-ovarian and intra-ovarian regulatory systems underpin the accelerated fall in AMH/follicle during the transition to menopause., Competing Interests: The authors have nothing to disclose., (© 2020 The Authors. Endocrinology, Diabetes & Metabolism published by John Wiley & Sons Ltd.)
- Published
- 2020
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