Normal Ranges for Anti-Müllerian Hormone (AMH)
AMH levels vary significantly by age, with no single universal "normal" range—age-specific reference ranges must be used, and values decline progressively from reproductive years through menopause.
Age-Specific Reference Ranges
The most clinically useful approach is to apply age-stratified reference ranges, as AMH declines exponentially with advancing age 1:
Reproductive Age Women (20-50 years)
Based on population studies in healthy women:
- Ages 20-25 years: 10.63-55.64 pmol/L (approximately 1.5-7.9 ng/mL) 2
- Ages 26-30 years: 3.74-61.88 pmol/L (approximately 0.5-8.8 ng/mL), median 20.89 pmol/L 2
- Ages 31-35 years: 5.49-47.56 pmol/L (approximately 0.8-6.8 ng/mL), median 19.92 pmol/L 2
- Ages 36-40 years: 2.15-48.91 pmol/L (approximately 0.3-7.0 ng/mL), median 13.71 pmol/L 2
- Ages 41-45 years: 0.92-41.26 pmol/L (approximately 0.1-5.9 ng/mL), median 9.24 pmol/L 2
- Ages 46-50 years: 0.14-5.10 pmol/L (approximately 0.02-0.7 ng/mL), median 0.68 pmol/L 2
Alternative Reference Ranges from Chinese Population
A large nationwide study provides slightly different ranges 3:
- Ages 20-25 years: 2.06-12.66 ng/mL (median 6.23 ng/mL) 3
- Ages 25-30 years: 1.77-13.83 ng/mL (median 5.65 ng/mL) 3
- Ages 30-33 years: 1.48-11.45 ng/mL (median 4.55 ng/mL) 3
- Ages 33-37 years: 0.87-9.76 ng/mL (median 3.74 ng/mL) 3
- Ages 37-40 years: 0.56-9.49 ng/mL (median 2.78 ng/mL) 3
- Ages 40-55 years: 0.08-5.70 ng/mL (median 1.09 ng/mL) 3
Critical Thresholds for Clinical Decision-Making
Low AMH (Diminished Ovarian Reserve)
- Below 1.0 ng/mL (7.14 pmol/L): Indicates significantly diminished ovarian reserve 1
- Below 1.56 ng/mL: May predict poor response to ovarian stimulation (fewer than 5 oocytes) 4
Elevated AMH (PCOS Spectrum)
- Above 5 ng/mL: Strongly associated with PCOS features 5
- Above 10 ng/mL: Over 97% of women have PCOS, with greater severity of oligoamenorrhea and polycystic ovarian morphology 5
- Diagnostic thresholds for PCOS in adults: 10-57 pmol/L (approximately 1.4-8.1 ng/mL), though significant heterogeneity exists 1
Important Clinical Caveats
Assay Variability
Major limitation: Significant technical variability exists between different AMH assays, with older DSL and IOT assays no longer marketed and limited data on newer automated platforms 1. International standardization is lacking, making direct comparison between laboratories problematic 1.
Geographic and Ethnic Differences
AMH levels show substantial geographic variation—North Indian women aged 22-30 years have significantly higher levels (4.4 ng/mL) compared to South Indian women (2.04 ng/mL) of the same age 6. Apply population-specific reference ranges when available.
Life Stage Considerations
- Adolescents: AMH levels are naturally elevated and overlap considerably between those with and without PCOS, making interpretation unreliable within 8 years post-menarche 1
- Perimenopausal women: AMH declines sharply and approaches undetectable levels after menopause 1
Not Recommended for Diagnosis
Current international guidelines do not support using AMH alone for PCOS diagnosis due to significant overlap between cases and controls, lack of standardized cut-offs, and moderate-to-high risk of bias in existing studies 1. AMH should be interpreted alongside clinical features (hyperandrogenism, ovulatory dysfunction) and ultrasound findings when appropriate 1.
Correlation with Other Markers
AMH positively correlates with antral follicle count, testosterone, LH, and progesterone levels, while negatively correlating with BMI and FSH 3. These relationships remain significant after controlling for age and BMI (except prolactin) 3.