AMH in PCOS: Controlling the ovary, placenta, or brain?

Abstract

Polycystic ovary syndrome (PCOS) is a very heterogeneous disease of which the exact pathophysiological mechanisms remain unknown. In PCOS, serum anti-Müllerian hormone (AMH) levels are significantly increased. AMH is a member of the transforming growth factor b family and is expressed by growing follicles in the ovaries. In PCOS, the transcriptional regulation of AMH and AMHR2 is altered, increasing and prolonging its temporal expression pattern. Moreover, the recently discovered extragonadal effects of AMH suggest that there might be a crosstalk between the ovary-placenta-brain. This review summarizes the recent findings concerning AMH and its role in the etiology of PCOS.

Unravelling Polycystic Ovary Syndrome and Its Comorbidities

“… 30 Further insights into the possible role of both neuroendocrine and local ovarian factors of AMH have provided the genesis of abnormal GnRH activity and resultant increases in LH and androgens. 31 Moreover, increased maternal AMH levels (which typically decrease during pregnancy in women with normal fertility) decrease placental Cyp19a1 expression, preventing aromatization of elevated maternal testosterone levels, which, in turn, results in a hyperandrogenic intrauterine environment, masculinization of the female fetus, 32 and a PCOS-like reproductive and neuroendocrine phenotype in adulthood. 33 …”

Anti-Müllerian Hormone in Pathogenesis, Diagnostic and Treatment of PCOS

“…A much higher expression of AMH, which is possible to measure in the blood, is observed in preantral and small antral follicles with a 2-4 mm diameter [13]. AMH expression is not observed in large antral follicles, although its trace expression is observed in a preovulatory follicle, though this is not possible to measure in the blood [11][12][13][14]. The role of AMH in folliculogenesis is based on inhibition of primary follicle recruitment through its paracrine effect and inhibition of selection from a pool of small antral follicles through gonadotropin recruitment [4,9].…”

“…AMH is involved in developing ovarian follicles and influences the hypothalamicpituitary-gonadal (HPG) axis at various stages of development [12]. Simultaneously, the regulation of AMH production may depend on many intracellular and extracellular signals.…”

“…The serum AMH concentration reflects the ovarian follicle pool with a strong dependence on the number of antral follicles in the early follicular phase of the menstrual cycle [12][13][14]. Therefore, a low antral follicle count may result in low serum AMH levels.…”

“…Therefore, blood samples can be taken on any day of the cycle [4]. It should be emphasized that AMH is a recognized biomarker of female reproductive potential, reflecting the number of primary follicles and their response to exogenous gonadotrophins [1,12,14].…”