Interactions between serum FSH, inhibin B and antral follicle count in the decline of serum AMH during the menstrual cycle in late reproductive age

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