Their study found that the average difference between the age predicted by the test and the actual age a woman reached menopause was about four months, while the maximum margin of error was between three and four years. If the accuracy of the test is confirmed in larger studies, women could take the test early on their reproductive life to find out their expected age at menopause, knowledge that would help them plan when to start a family, said researcher Dr. Fahimeh Ramezani Tehrani, president of the Reproductive Endocrinology Department of the Endocrine Research Centre and associate professor at Shahid Beheshti University of Medical Sciences in Iran.
The test measures concentrations of anti-Mullerian Hormone (AMH), a hormone produced by cells in the ovaries. AMH controls the development of ovarian follicles, which contain a woman's eggs. For their research, Tehrani and colleagues analyzed blood samples taken every few years from the participants, who also had regular physical examinations and provided information about their socioeconomic background and reproductive history. Among the study findings: • Early menopause (before age 45) was predicted by AMH levels of 4.1 nanograms or less per milliliter of blood at age 20, 3.3 nanograms per milliliter at age 25, and 2.4 nanograms per milliliter at age 30. • Menopause after age 50 was predicted by AMH levels of at least 4.5 nanograms per milliliter at age 20, 3.8 nanograms per milliliter at age 25, and 2.9 nanograms per milliliter at age 30. • The average age for menopause among women in the study was about 52.