AMH Explained: What It Means, How to Use It, and Its Limits

Anti-Müllerian hormone (AMH) is secreted by the granulosa cells of small antral and pre-antral follicles and is the most reliable serum marker of ovarian reserve currently available. But it is frequently over-interpreted — particularly in predicting natural conception or IVF live birth rates.

Reference Ranges

AMH is measured in either pmol/L or ng/mL (1 ng/mL = 7.14 pmol/L). Typical ranges by age: under 35 years, normal is 14–48 pmol/L; ages 35–40, 7–28 pmol/L. Low AMH (<5 pmol/L) suggests diminished ovarian reserve; high AMH (>40 pmol/L) raises OHSS risk and may indicate PCOS.

What AMH Predicts Well

AMH is reliable for predicting ovarian response to stimulation (egg yield), timing of menopause, and risk of OHSS. It guides starting gonadotrophin dose selection and informs whether a freeze-all strategy is advisable.

What AMH Does Not Predict

AMH does not predict egg quality, embryo competence, or live birth rate independently of age. A woman with a low AMH can have excellent quality oocytes; a woman with a high AMH may produce chromosomally abnormal embryos if she is 42. Age remains the strongest predictor of IVF success.

Common Clinical Mistakes

Treating low AMH as a reason not to pursue IVF (poor prognosis does not mean zero chance). Counselling a 35-year-old with AMH of 4 pmol/L to "give up" is incorrect — natural IVF cycles or banked embryos from a younger donor can still succeed. Conversely, assuming high AMH guarantees success regardless of age is equally misleading.