Clinical Information

Antimullerian hormone (AMH), also known as Mullerian-inhibiting substance, is a dimeric glycoprotein hormone belonging to the transforming growth factor-beta family. It is produced by Sertoli cells of the testis in male patients and by ovarian granulosa cells in female patients. Expression during male fetal development prevents the Mullerian ducts from developing into the uterus, resulting in development of the male reproductive tract. In the absence of AMH, the Mullerian ducts and structures develop into the female reproductive tract. AMH serum concentrations are elevated in boys under 2 years old and then progressively decrease until puberty when there is a sharp decline. In female individuals, serum AMH concentrations are very low at birth, peaking after puberty, and decrease progressively thereafter with age, eventually becoming undetectable at menopause.

Because of the gender differences in AMH concentrations, its changes in circulating concentrations with sexual development, and its specificity for Sertoli and granulosa cells, AMH measurement has utility in the assessment of gender, gonadal function, fertility, and as a gonadal tumor marker.

In female individuals, AMH is considered an ovarian reserve marker. It correlates with the primordial follicle pool, has an inverse correlation with chronologic age, predicts ovarian response in assisted reproductive therapy, and has been suggested to be predictive of the timing of the onset of menopause. In contrast to other markers of ovarian reserve that show significant fluctuations during the menstrual cycle, serum AMH concentrations have been shown to be relatively stable. Women with higher concentrations of AMH have a better response to ovarian stimulation and tend to produce more retrievable oocytes than women with low or undetectable AMH. Women at risk of ovarian hyperstimulation syndrome after gonadotropin administration can have significantly elevated AMH concentrations. Polycystic ovarian syndrome can elevate serum AMH concentrations, because it is associated with the presence of large numbers of small follicles.

AMH measurements are commonly used to evaluate testicular presence and function in infants with intersex conditions or ambiguous genitalia and to distinguish between cryptorchidism and anorchia in male infants.

Serum AMH concentrations are increased in some individuals with ovarian granulosa cell tumors, which comprise approximately 10% of ovarian tumors. AMH, along with related tests including inhibin A and B (INHA / Inhibin A, Tumor Marker, Serum; INHB / Inhibin B, Serum; INHAB / Inhibin A and B, Tumor Marker, Serum), estradiol (EEST / Estradiol, Serum), and cancer antigen 125 (CA25 / Cancer Antigen 125 [CA 125], Serum), can be useful for diagnosing and monitoring these individuals.