Hormones
AMH
Hormone from the egg follicles that gives an estimate of the egg reserve; not a fertility test.
Everything about this testWhat it measures
AMH (anti-Müllerian hormone) is made by the cells around the small egg follicles in the ovaries. The more of those small follicles there are, the higher the value; that is why AMH gives an estimate of the egg reserve. With age, the reserve decreases and AMH falls; after menopause, the value is very low. AMH says nothing about the quality of the eggs.
- An estimate of the egg reserve before IVF treatment or egg freezing, to estimate the response to hormone stimulation
- A strongly reduced egg reserve in women under 40 who no longer have periods (early menopause), together with FSH and estradiol
- A reduced egg reserve after treatment with chemotherapy or radiotherapy
- A raised value that fits many small follicles, as in PCOS (polycystic ovary syndrome); on its own not enough to diagnose PCOS
High
A high AMH fits many small follicles in the ovaries. This is common in young women and in PCOS, especially together with irregular periods, acne or excess hair growth. According to the Dutch PCOS guideline (NVOG, 2023), AMH should not be used as the only test to diagnose PCOS, nor instead of an ultrasound, because the values of women with and without PCOS overlap strongly and the measurement methods differ too much. A high AMH does not mean that you are extra fertile or that you can safely postpone having children.
Low
A low AMH means that there are fewer small follicles than average. This says little about the chance of getting pregnant: women of the same age have on average the same chance per month, regardless of their AMH, and pregnancies also occur with a low AMH, especially in young women. A low AMH also does not predict when menopause will start; the test is too inaccurate for that. If you use the contraceptive pill, the result may be unreliable. In women under 40 who no longer have periods, a low or unmeasurable AMH together with a high FSH and a low estradiol fits early menopause.
Preparation
- Do you take biotin (vitamin B8, often in hair and nail supplements)? Stop at least 2 days before the sample is taken, or 4 days for a high dose.
If your result is abnormal
With a low AMH without symptoms, no follow-up testing is needed according to the guidelines. When periods stop under the age of 40, the GP has FSH and estradiol measured, repeats them after at least 4 weeks and, with abnormal values, refers you to a gynecologist. With a high AMH together with an irregular cycle and symptoms of too much male hormone, an assessment for PCOS follows, with cycle data, hormone testing and, if needed, an ultrasound.
Reliability
AMH is a reasonable measure of the number of small follicles, but not a fertility test. According to the guideline on initial fertility assessment of the Dutch Society of Obstetrics and Gynecology (NVOG), AMH does not predict the chance of a natural pregnancy, not even in women without fertility problems; even when a wish to have children remains unfulfilled, the value says little about this. According to the joint position of the NVOG, the Dutch College of General Practitioners (NHG) and Freya from 2022, home fertility tests can give false reassurance or cause unnecessary worry. AMH is mainly useful around IVF treatment or egg freezing, to estimate how many eggs stimulation will yield; even then, the value does not predict whether a child will be born.
Limitations
- Hormonal contraception can give an unreliable result.
- In PCOS, AMH is often high; the value then says little about fertility.
- Measurement methods differ per laboratory, so cut-off values from research or from another laboratory cannot simply be used.
- The value depends strongly on age and can only be interpreted against the reference values for that age.
How common is this
On average, women reach menopause around the age of 51. In about 1 in 100 women this happens before the age of 40 (early menopause), and in about 5 in 100 before the age of 45. How often a low AMH without symptoms occurs is not well known; on its own, it is not a condition.
Who is this useful for
Useful around fertility treatment such as IVF, before egg freezing, after treatment with chemotherapy or radiotherapy, and in women under 40 who no longer have periods, together with FSH and estradiol. Not useful for determining whether you can get pregnant, whether you can postpone having children, or when you will reach menopause: AMH is not suitable for that, because the result does not predict it, and age remains the most important factor. When a wish to have children remains unfulfilled, AMH also does not answer the question of whether there is a cause; testing for that looks at the cycle, a past chlamydia infection and the semen.
Downsides and risks
- A normal or high result can give a false sense of security and seem like a reason to postpone having children, while the chance of pregnancy falls from about age 30, and faster from age 35, regardless of the result.
- A low result can cause unnecessary worry, pressure to get pregnant sooner or to freeze eggs, and unnecessary medical testing.
Sources
- NVOG, NHG en Freya: Standpunt Thuistesten voor fertiliteit (2022)
- NVOG, Richtlijn Oriënterend fertiliteitsonderzoek: module AFC en Anti-Müllerse hormoon
- NVOG, Richtlijn PCOS (adaptatie internationale richtlijn, 2023): module Anti-Müllers hormoon (AMH)
- Freya: Is de anti-Müller hormoon (AMH) test een betrouwbare vruchtbaarheidstest? (2024)
- Erasmus MC, patiëntenfolder Premature ovariële insufficiëntie (vervroegde overgang)
Always discuss an abnormal result with your GP. If a result is strongly abnormal, we try to reach you as soon as possible. Read your result yourself as well and contact your GP if in doubt. A test does not make a diagnosis. Read more about risks and results