Detailed definition
Anti-Müllerian hormone (AMH), also called Müllerian inhibiting substance, is a glycoprotein produced by Sertoli cells in the testis (where in fetal life it causes regression of the Müllerian ducts) and by granulosa cells of preantral and small antral follicles in the ovary. In women, serum AMH correlates with the number of small growing follicles and is widely used as a marker of ovarian reserve in fertility evaluations. AMH peaks in the mid-20s and declines progressively with age, becoming undetectable in postmenopause. Unlike FSH, AMH does not vary substantially across the menstrual cycle, which makes single-day measurement clinically useful. Very low AMH in a woman in her 40s is consistent with limited remaining ovarian reserve and approaching menopause; undetectable AMH is consistent with established postmenopause. AMH cannot precisely predict the date of the final menstrual period, but it provides a useful trajectory marker.
Why it matters in menopause
AMH is increasingly ordered to give women a sense of how much "menopause runway" remains, particularly for fertility planning. For women asking "am I in perimenopause?" with typical-age symptoms and irregular cycles, AMH does not change management. For women under 40 with concerning symptoms, AMH can support a workup for POI alongside FSH and estradiol.
Related terms
Sources
External references: Wikipedia.