A simple blood test may be available to help women know when they are approaching menopause. According to collaborating scientists from medical centers in Australia and the Netherlands, measuring blood levels of anti-Mullerian hormone (AMH), a reproductive hormone secreted by the ovaries, can estimate how close a woman is to entering menopause.
Follicle cells in the ovaries produce AMH to nurture and to stimulate egg production. The number of follicles within each ovary is directly linked to AMH levels in the blood and to fertility. The more follicles present, the higher the AMH blood level and the greater the chance a woman has at conceiving.
Scientists began looking at anti-Mullerian hormone as predictor for menopause because the ovaries secrete the hormone at a constant rate during a woman’s monthly cycle, levels appear to drop with age and AMH is not affected by oral contraception. The current study published in the Journal of Clinical Endocrinology and Metabolism compared the levels of AMH in 144 premenopausal women with more than 3,000 postmenopausal women to come up with a statistical curve to estimate when a women enters menopause based on AMH measurements.
Dr. Jeroen van Disseldorp, lead author, concludes that the “AMH level appears to be the best marker of the aging process in premenopausal women.”
Other predictors of fertility or menopause such as age or level of other reproductive hormones like follicle stimulating hormone (FSH) or estrogen are comparatively imprecise. Menopause is usually defined as the point when a woman in her 40’s or older has gone twelve months without having her period. Since there is a wide variation in age of menopause with it occurring in women anywhere from 40 to 60 years old, it’s impossible to predict when menopause will happen to a particular woman solely based on her age.
Likewise, hormone levels of FSH or estrogen fluctuate widely during the normal course of a woman’s monthly cycle and can be influenced by birth control medications making these hormones less than ideal predictors of menopause. Ultrasound is another way many IVF clinics estimate the number of follicles within the ovaries, but the images may not always be clear enough to provide an accurate count.
The authors admit that more study is needed to be sure their model of menopause prediction based on AMH levels applies to all ethnic groups. They also point out that the AMH test would be most effective in women over 30 years old since AMH levels are fairly stable in women up to that age.
AMH assays are not readily available yet and are more costly than current fertility tests. Still, according to Dr. van Disseldorp “predicting menopause might become more and more important in the future as women continue to delay childbearing,” and AMH testing may become an important part of that process.
Article Links:
van Disseldorp, J., et al, 2008. “Relationship of Serum Anti-Mullerian Hormone Concentration to Age of Menopause,” J Clin Endocrin Metab.
http://jcem.endojournals.org/cgi/content/short/jc.2007-2093v1
Related Links:
May 2008. Time. “A Blood Test to Predict Menopause”
http://www.time.com/time/printout/0,8816,1736472,00.html#
WebMed, 2006 on line article “Sexual Health: Your Guide to Female Infertility.”
http://www.webmd.com/infertility-and-reproduction/guide/female-infertility