Anti-mullerian hormone (AMH) level is now routinely used to evaluate ovarian reserve. AMH levels decrease with age and are a more consistent predictor of “ovarian age” than antral follicle count on ultrasound, inhibin b, or FSH levels. The ovary produces AMH and this is confirmed by the fact that AMH levels are undetectable after surgical removal of ovaries as well as menopause. It is therefore reasonable to ask, “Does AMH level predict age at menopause?”
The answer is a qualified yes! But this is true only in older women. Freeman et al. from the University of Pennsylvania, Philadelphia, studied this very question as part of the Penn Ovarian Aging Study (Freeman et al., J Clin Endocrinol Metab 2012;97:1673-80). They studied 401 older women (mean age 41.47 y) with a median AMH level of 0.68 ng/mL over a 14-year period. AMH strongly predicted time to menopause; age further improved predictions. Among women with a baseline AMH level below 0.20 ng/ml, the median time to menopause was 5.99 yr [95% confidence interval (CI), 4.20–6.33] in the 45- to 48-yr age group and 9.94 yr (95% CI, 3.31–12.73) in the 35- to 39-yr age group. With higher baseline AMH levels above 1.50 ng/ml, the median time to menopause was 6.23 yr in the oldest age group and more than 13.01 yr in the youngest age group. Smoking significantly reduced the time to menopause (hazard ratio, 1.61; 95% CI, 1.19 –2.19; P = 0.002).
These data may not be applicable to younger women. I have addressed this in another blog where a recent study showed young women with low AMH levels had a good chance of natural conception. The authors emphasize that these are findings from generally healthy women and may not be applicable to women with ovulatory infertility, menstrual cycle irregularities, or other health problems. Women who had disease conditions such as endometriosis or polycystic ovary syndrome were not included in this study. Another limitation of their findings is that AMH levels can vary from lab to lab and their numbers should not be taken literally. This data should not be used to counsel individual with a precise estimate as to when they will go through the menopause.
Dr. Karande is Board Certified in the specialty of Obstetrics and Gynecology as well as the subspecialty of Reproductive Endocrinology and Infertility. He is a Fellow of the American College of Obstetricians and Gynecologists and Member of the American Society for Reproductive Medicine.