By: Red Hot Mamas
Published: July 13, 2010
“Tick tock, tick tock, hickory dickory dock, chime the sounds of the biological clock. The sound usually starts resonating in the late 20s for women. This is when the pressure to start a family and have children by the age of 30 can become overwhelming.
But, what happens when you decide to postpone the time you start a family? Wouldn’t you want to know when the biological clock plans to stop ticking? Some women are surprised to find out they can’t have children because they are already sterile. With a new test, delaying the start of a family may become easier. According to a new Dutch study, a simple blood test can now accurately predict the age of the onset of menopause.
Rewind back to biology class for a minute and you’ll remember that women are born with a finite number of eggs. Eggs develop in fluid filled structures in the ovaries called follicles. Follicles can be seen on an ultrasound. Throughout life, they constantly lose eggs until they completely disappear at menopause.
The new Dutch study (released on April 29, 2008 in the Journal of Clinical Endocrinology & Metabolism ) examined the levels of the anti-Müllerian hormone (AMH) in the blood. Evidently, this hormone can be used as a biomarker for the number of follicles present in the ovaries. By taking an inventory of the amount of follicles present in your body, you can predict the age you’re going to reach menopause.
AMH is easy to measure and doesn’t vary much, making it a reliable method of measuring the reserve of follicles in the ovaries. When the reserve is depleted, menopause begins. Researchers claim AMH is even more effective than follicle-stimulating hormone (FSH) tests. FSH levels tend to fluctuate with the menstrual cycle whereas AMH does not.
For the Dutch study, AMH measurements were collected from 144 healthy, Caucasian women ages 25-46. The median age for the onset of menopause turned out to be 51 years. Based on the findings, the study estimated the distribution of age at menopause in a group of 3,384 postmenopausal women between the ages of 50 and 70.
AMH proved to be a precise predictor of menopause for women in their 30s and up. Women with higher or lower AMH for their age would have an earlier or later menopause, respectively. The next step is to see if the model is correct and women actually reach menopause at the age predicted.
Menopause is defined as the last menstrual period and, as mentioned, has a median age of 51.4 years. Women who voluntarily defer pregnancy should be aware that there is an age-related decline in the ability to conceive. Fertility begins to decline at age thirty but may be present until the last menstrual period when ovarian function has ceased.
The growing rate of infertility is due to women’s choosing to delay pregnancy until later in life when fertility problems tend to arise. At menopause, women’s ovaries lose their ability to produce eggs. Menopause sometimes occurs earlier and it is considered “premature” if it occurs in women before age 40. This may be due to an autoimmune disorder, or simply due to genetics. Smoking also may bring on early menopause. Premature ovarian failure can also occur in women who have anticancer treatments (chemotherapy and/or radiation).
Deciding when to have children is greatly dependent on when the fertility window actually occurs. You may not be able to stop the tick tock of your clock but, at least you’ll be able to plan a family before it stops completely.
Boyles, S. Hormone May Predict Age at Menopause , WebMD: April 30, 2008.
Raymond, J. Biological Alarm Clock, Newsweek: May 6, 2008.
Smith, M., Hormone May Be Guide to Biological Clock, MedPage Today: April 29, 2008.
Van Disseldorp, J. Journal of Clinical Endocrinology & Metabolism, online edition released April 29, 2008.