Reference Ranges of Serum Anti-Müllerian Hormone in Healthy Reproductive-aged Omani Women

Anti-Müllerian hormone (AMH), a glycoprotein that belongs to the transforming growth factor-beta superfamily, is important for women's health. We aimed to determine the age-specific reference range of serum AMH in healthy Omani women from reproductive ages to menopause.

This cross-sectional cohort study was conducted among a group of healthy 20-50 years old Omani women. The participants were required to have body mass index < 32 kg/m², regular periods, no history of chronic illness, polycystic ovary syndrome, or gynecological operation. They were also required to not be using any hormonal contraceptive. Serum concentrations of AMH, follicle-stimulating hormone, luteinizing hormone, progesterone, and hemoglobin A_1c were measured. AMH-age nomogram and AMH levels were compared between the six selected age groups.

The subjects were 319 Omani women aged 20-50 years. Serum AMH concentrations were found to decrease progressively with increasing age. An exponential model defined as √AMH = 479.02 × 0.91^age was selected to explain the reduction in AMH with age (R² = 0.298). The median AMH levels were 26.61 pmol/L for those aged 20-25 years, 20.89 pmol/L for 26-30 years, 19.92 pmol/L for 31-35 years, 13.71 pmol/L for 36-40 years, 9.24 pmol/L for 41-45 years, and 0.68 pmol/L for 46-50 years. The recommended 2.5^th to 97.5^th percentiles of AMH level, as reference ranges for various age groups, were found to be: 10.63-55.64 pmol/L (20-25 years), 3.74-61.88 pmol/L (26-30 years), 5.49-47.56 pmol/L (31-35 years), 2.15-48.91 pmol/L (36-40 years), 0.92-41.26 pmol/L (41-45 years), and 0.14-5.10 pmol/L (46-50 years).

This study (the first in Oman) determined the age-specific reference ranges of serum AMH in healthy Omani women in the age range of 20-50 years.