What is ovarian
ageing?
Ovarian ageing is a reduction in the quantity and quality
of the oocytes in the ovaries. Although the average age of menopause is 51
years, approximately 1 in 10 women reach menopause before the age of 45 and
approximately 1 in 100 women reach menopause prior to the age of 40 years. It
has been postulated that fertility reduces 13 years before menopause, i.e. 1 in
10 women will have reduced fertility by the age of 32 years. A series of
ovarian reserve tests have been used to predict ovarian ageing or poor ovarian
reserve. The main purpose of these tests is to determine reduced fertility at a
stage when appropriate treatment can be instituted.
AMH as a test of
ovarian reserve
Several studies have demonstrated that AMH is a better
marker of ovarian reserve compared with age alone or other markers described in
the literature such as basal FSH, estradiol and inhibin B. AMH is a serum blood
test with a stable value obtainable throughout the menstrual cycle, which is a
major advantage over other markers such FSH and inhibin, which can only be done
at a certain time in the menstrual cycle. In addition, being a blood test, it
has advantages over ultrasound (USG) based on antral follicle count (AFC), as
trans-vaginal ultrasound is considered an invasive examination. AMH is used
most commonly in an IVF setting, being routinely used in certain centers.
Recent Study
The new study confirmed the previously obtained results,
that doctors may be able to predict as early as a woman's late 30s the age at
which she will eventually experience menopause, based on how quickly the levels
of one hormone in her blood change.
Researchers studied 293 women in their 30s and 40s,
taking blood samples over several years to measure their levels of
anti-mullerian hormone (AMH), which is produced by the ovaries. They found that
the amount of year-to-year change in AMH levels provided a good predictor of
when the women experienced menopause.
Currently, the only way to estimate when a woman will
enter menopause is by using her age — the average age that menopause occurs is
51, but women can also experience the change in their 40s or late 50s, per the
National Institutes of Health.
The new study showed that AMH levels explained nearly 82
percent of the variability between women.
Additionally, the researchers found that the women whose
AMH levels changed the most reached menopause two years earlier on average,
compared with women whose levels changed the least.
"AMH levels have added another indicator," of
the age menopause will begin, said study author Ellen Freeman, a research
professor at the University of Pennsylvania. This is helpful because age
"is not a wonderfully accurate predictor, it's just an available
predictor," she said.
The women in the study underwent blood tests every nine
months for five years, and researchers followed them for up to 14 years later
to see when they actually entered menopause.
It was known that AMH levels decrease as women age and
approach menopause. The researchers found that combining a woman's age, hormone
levels and the extent to which hormone levels were changing provided the most
accurate indicator of the age at which she'd begin menopause.
Predicting how far a woman is from entering menopause
could be useful to women with fertility problems, and those facing an increased
risk of other health issues that may be affected by menopause, such as
osteoporosis or heart disease, Freeman said.
But, she noted, the test is intensive, requiring patients
to submit to repeated blood tests over a 3- to 5- year span, which may be
difficult. Furthermore, while the study showed that the blood test predicted
the menopause age for groups of women, it may be less accurate for any one
individual, she said.
The test is not likely to work in women younger than their
mid-30s, because AMH levels don't start declining until women are at least that
age, Freeman said. "In our sample, the youngest women were 35."
Kathleen Hill-Besinque, a women's health researcher and
associate pharmacy professor at the University of Southern California, said the
results were scientifically interesting, but added that she wasn't sure when
this test might become useful in a clinical setting.
Additionally, the study researchers didn't compare their
method of calculating menopause age to calculations based on the ages a woman's
mother or sisters experienced menopause, Hill-Besinque said. The age of
menopause is believed to have a genetic component.
However, Besinque said that the test could be used to
help women with other health problems, or even further down the line, to
encourage women to become healthier to delay menopause. For example, women who
smoke tend to go through menopause sooner, and showing them how the habit
affects their age of menopause could have "a tangible impact on their
health," she said.
Test Details
Why Get Tested?
In women, to evaluate ovarian function and fertility;
sometimes in the evaluation of polycystic ovarian syndrome (PCOS) or to
evaluate the effectiveness of ovarian cancer treatment; in an infant, to
evaluate the presence of external sex organs that are not clearly male or
female (ambiguous genitalia) and/or function of the testicles in an infant boy
When to Get Tested?
When a health practitioner wants to evaluate a woman's
fertility, predict onset of menopause, or suspects PCOS; sometimes prior to
some assisted reproductive procedures; periodically when a woman is undergoing
treatment for an AMH-producing ovarian cancer; when it is suspected that the
testicles of an infant boy are absent or not functioning properly
Sample Required?
A blood sample drawn from a vein in your arm
Test Preparation
Needed?
None
Sources and
Additional Information:
