AMH - ?The ultimate egg timer test
Women are born with all of the eggs that they will ever have, as opposed to men who are able to keep generating sperm through their lives. The decline in the egg numbers roughly reflects the decline in fertility as women age, and when they run out a woman undergoes menopause. One of the holy grails for fertility research (and perhaps for real gender equality in reproductive choice!) is to find a test that allows women to know when their fertility is going to end. The AMH test is the closest science has come to this test, but it’s not quite yet proving to be the perfect test we’d hoped for.
What is AMH?
AMH (or Anti Mullerian Hormone) is a hormone secreted by ovarian follicles (eggs surrounded by supporting cells) in women. It is secreted in to the blood stream by the follicles that are in reserve, or in the very early stages of developing into mature follicles that release eggs at ovulation. When blood levels are measured, these are therefore thought to reflect the reserve of eggs that a woman has left. We are not entirely sure of the role of AMH in the ovary, but it may be involved in the process of selecting one egg at a time for ovulation. A big advantage of AMH over other tests of egg reserve is that it can be done at any time of the menstrual cycle or when a woman is on the oral contraceptive pill.
What do we know about the significance of AMH levels?
First of all, it is important to interpret AMH levels according to your age range. Many laboratories report a range for all age groups, but it is more relevant if it is compared to other women of your age. Current research tells us that:
Low AMH levels for your age are associated with
An earlier menopause (Those in the 5th percentile for their age group have been shown to undergo menopause approximately 3 years earlier than average)
An increased risk of a poor response to IVF or egg freezing technologies (only developing small numbers of eggs). However, some women with a low AMH result may still respond normally.
High AMH levels are associated with
Polycystic ovarian syndrome
A higher risk of ovarian hyperstimulation syndrome (OHSS) with IVF
AMH levels DO NOT tell us
Exactly how many eggs are left or the exact time fertility is going to run out
That there is a reduced chance of natural pregnancy if you have not yet attempted to become pregnant.
That there is no hope of IVF working.
We are still unsure
Whether AMH reflects the quality of eggs in terms of development of embryos or miscarriage rates. Some early studies have shown that AMH does NOT seem to be associated with the quality of eggs, but further research needs to be done in this area.
Should I get an AMH test done?
An AMH is very useful test for the following groups
- Women who have been trying to conceive for the recommended time (12 months if <35, 6 months if >35), basic investigations are normal, and unsure when to take the next step, for example in moving on to IVF.
- Women at risk of premature menopause (for example those who have undergone cancer treatments in childhood or adolescence).
- Women about to undergo chemotherapy to help in the prediction of this affecting their fertility.
Fertility specialists often order AMH as part of the diagnostic workup for infertility and to tailor IVF treatment regimes.
If you are a single woman think very carefully before having an AMH done. Would you change anything if it came back as a low result? Would you consider sperm donation or egg freezing?
What should I do if I have a low AMH
If you want to have children, the best advice is to try for a pregnancy as soon as possible if you are in the right social circumstances to do so.
If you have already been trying to conceive for 6-12 months, it is important to get the advice of a fertility specialist.
If you do not have a stable male partner, you may want to enquire about egg freezing or sperm donation.