Did you know that we are born with a predetermined or finite number of potential eggs? When a girl is born she is born with about a million eggs, by the time she reaches the age of 13 (puberty) she’s down to about 400,000. During a woman’s reproductive years those numbers continue to decrease and by the time that 13 year old is 30 that number has diminished by a whopping 90%! And get this — by the time we hit menopause we have actually less than 1000 eggs left, and most of them aren’t good. In fact, some people refer to what’s left as “ovarian dust”
That stinks if you ask me.
Our reproductive age is often older than how old we really are – for those women who are unable to have children with their own eggs they turn to egg donors to help create their family.
Typically egg donors are tested medically with a blood test administered on days one, two, or three of the menstrual cycle called FSH (Follicle Stimulating Hormone). This measures the egg reserve in an egg donors ovaries, that along with an ultrasound which will look at something called an Antral Follicle Count (or resting follicle count) which will tell the doctor how many potential eggs an egg donor might produce on her next cycle. Because these tests are accurate on days one, two, and three of an egg donors menstrual timing is crucial.
However, there’s newer method that’s been developed called AMH or Anti-Mullerian Hormone blood test. This test measures the amount of AMH in an egg donor’s blood stream. AMH, or Anti-Mullerian hormone is a substance produced by granulosa cells in ovarian follicles which are specific cells which surround each and every egg on a woman’s ovary. The more eggs, the more granulosa cells, and the more cells the more AMH – make sense?
The cool part about this test is that the production decreases and then stops as our follicles grow. So for instance, in follicles over 8mm there is almost no AMH that’s made. Because of that the levels are always constant and the AMH test can be performed any day of the egg donor’s cycle.
That means the intended parent doesn’t need to wait for the donor’s period to start.
Many refer to the AMH as the “egg timer test” because when you combine the AMH and FSH together with an antral follicle count this together can provide the fertility clinic with a good measurement of an egg donor’s ovarian reserve. In other words – they can get a picture of how they think a donor will respond to the stimulation drugs for an egg donor cycle.
There has to be a catch or a down side right?
Well yes, and no. It’s super important to remember that while this test can tell a donor how many eggs she may have left we still don’t have a fool proof way of knowing the quality of those eggs. We can’t know that until after fertilization when we examine embryos. But, — having more eggs at the IVF egg retrieval gives your clinic more to work with – so they are more likely to have at least a few high quality embryo available for transfer back to the intended mothers uterus.
What is a normal AMH level?
There are a few issues involved with interpretation and determination of AMH hormone levels. Because the test has not been used routinely and consistently for past 50 years levels that would be deemed “normal” not every reproductive professional agrees with.
We made a little table below to show AMH interpretation guidelines for AMH levels across the board and most importantly:
Don’t spend too much time obsessing about the results below. Let your RE do the obsessing.
|Interpretation||AMH Blood Level|
|High (common with PCOS)||Over 3.0 ng/ml|
|Normal classic textbook.||Over 1.0 ng/ml|
|Low Normal-ish Range(maybe depending upon your egg donors FSH and AFC count)||0.7 – 0.9 ng/ml|
|Low (pass on this egg donor)||0.3 – 0.6 ng/ml|
|Very Low (pass on this egg donor)||Less than 0.3 ng/ml|
In an every changing world of technology we will learn more and more about AMH levels as we see more and more cycles occur.