Anti-Müllerian Hormone and Polycystic Ovary Syndrome in Women and Its Male Equivalent

Abstract

This article reviews the main findings on anti-Müllerian hormone (AMH) and its involvement in the pathogenesis of polycystic ovary syndrome (PCOS) and its male equivalent. In women, AMH is produced by granulosa cells from the mid-fetal life to menopause and is a reliable indirect marker of ovarian reserve. AMH protects follicles from atresia, inhibits their differentiation in the ovary, and stimulates gonadotrophin-releasing hormone neurons pulsatility. AMH overexpression in women with PCOS likely contributes to the increase of the follicle cohort and of androgen levels, leading to follicular arrest and anovulation. In the male, AMH is synthesized at high levels by Sertoli cells from fetal life to puberty when serum AMH falls to levels similar to those observed in women. AMH is involved in the differentiation of the genital tract during fetal life and plays a role in Sertoli and Leydig cells differentiation and function. Serum AMH is used to assess Sertoli cell function in children with disorders of sex development and various conditions affecting the hypothalamic-pituitary-testicular axis. Although the reproductive function of male relative of women with PCOS has been poorly investigated, adolescents have elevated levels of AMH which could play a detrimental role on their fertility.

Keywords: Müllerian inhibiting substance; anti-Müllerian hormone; male polycystic ovary syndrome equivalent; polycystic ovary syndrome.

Figure 1

Main AMHR2-expressing organs and effects of AMH in the gonads. AMH is mainly produced by the gonads (large blue arrows). AMHR2-expressing organs (thin arrows) are the placenta, the mammary glands, the uterus, and the ovaries in females, and the Müllerian ducts, the prostate, and the testes in males. AMHR2 is also expressed in the nervous system, the pituitary gland, the adrenals, and the pancreas in both sexes. In the ovaries, AMH represses aromatase, follicle sensitivity to FSH and follicle atresia. In the testes, AMH inhibits steroidogenesis.

Figure 2

Involvement of AMH in the pathogenesis of the PCOS. In women with PCOS, the increased AMH levels (brown arrows beside the women with PCOS) may contribute to the development of their ovarian defects by acting both at the ovary and hypothalamo–pituitary complex. In pregnant women with PCOS, the increased AMH levels (brown arrows beside the women with PCOS) may in addition participate to fetal hyperandrogenism by disturbing placenta steroidogenesis. 🡇: inhibitory effect of AMH, 🡅: stimulatory effect of AMH.