The role of anti-Müllerian hormone in the classification of anovulatory infertility

Abstract

Objective: The World Health Organization (WHO) has defined three classes of anovulatory infertility, based on serum gonadotrophin and oestradiol levels: low gonadotrophin and oestradiol levels in women with WHO 1 anovulation, normal hormone levels in WHO 2 anovulation and high gonadotrophin but low oestradiol levels in WHO 3 anovulation. The number of follicles on the ovary also seems to be different in the three classes of anovulatory infertility. Serum anti-Müllerian hormone (AMH) levels correlate well with the number of pre-antral and small antral follicles. The objective of our study was to investigate whether a single AMH measurement might simplify the classification of the WHO classes of anovulatory dysfunction.

Study design: In a tertiary hospital, 1863 patients with either oligomenorrhea or secondary amenorrhea were recruited. Standardized screening was performed, including transvaginal ultrasound and serum AMH measurement. Serum AMH levels were compared with those in 348 age-matched controls.

Results: Serum AMH levels were slightly elevated in women with hypogonadotropic anovulation (n=128) (P<0.001) as compared with controls. Normogonadotropic anovulatory women (n=1.465) had distinctly higher serum AMH levels than controls (P<0.001) and serum AMH levels were low in women with hypergonadotropic anovulation (n=270) (P<0.001). Although median AMH levels were distinctly different in each class of anovulatory dysfunction, serum AMH levels were comparable in hypogonadotropic women and normogonadotropic women without polycystic ovary syndrome.

Conclusion: The clinical applicability of serum AMH as a diagnostic tool to differentiate between the different classes of anovulatory dysfunction seems to be limited to the prediction of hypergonadotropic anovulation.

Keywords: Anovulation; Anti-Müllerian hormone; Follicles; Polycystic ovarian morphology.