Anti-Mullerian Hormone (AMH) became the trendy fertility test in the 2010s. It is now offered through direct-to-consumer labs, fertility clinics, and increasingly even general gynecology offices. The pitch is usually some version of “find out how many eggs you have left.” The reality, supported by a decade of careful research, is more nuanced and in some ways more reassuring than the marketing suggests.
This post covers what AMH measures, what it actually predicts, what it does not predict, and when testing it is genuinely useful.
What AMH is
AMH is a protein made by the granulosa cells in small ovarian follicles — specifically, the preantral and small antral follicles. The level in the bloodstream roughly reflects the size of the active follicle pool at any given moment.
Important properties:
- Stable across the cycle. Unlike FSH and estradiol, which fluctuate dramatically through the menstrual cycle, AMH is relatively stable. You can test it on any cycle day.
- Decreases with age. As the egg pool shrinks over reproductive life, AMH falls. Average values drop steadily from age 25 onward, with sharper declines after 35.
- Lowered by hormonal contraceptives. Combined hormonal contraception lowers measured AMH by roughly 20 to 30 percent. Levels recover within a few months of stopping.
- Not significantly affected by pregnancy. Pregnancy does not durably affect AMH.
- Elevated in PCOS. Polycystic ovaries have many more small follicles, so AMH is often 2 to 3 times higher than typical for age.
Age-adjusted AMH ranges
There is no single “normal” because age dominates. Approximate reference ranges (in ng/mL, the common US units; multiply by 7.14 for pmol/L):
- Age 25 to 30: 2.0 to 6.5 ng/mL.
- Age 30 to 34: 1.5 to 5.0 ng/mL.
- Age 35 to 39: 1.0 to 3.5 ng/mL.
- Age 40 to 42: 0.5 to 2.5 ng/mL.
- Age 43+: typically under 1.0 ng/mL.
Values consistently above the high end suggest PCOS or polycystic ovary morphology. Values below 1.0 ng/mL in someone under 35 may suggest diminished ovarian reserve.
These are population averages. There is wide individual variation, and different labs have different reference ranges depending on the assay used. Two assays from different labs can disagree by 20 to 30 percent.
What AMH does not predict
This is the most important section. AMH became popular partly because it was easy to measure and partly because the marketing implied that a lower number meant “running out of time.” The data do not support most of that.
AMH does not predict natural fertility
Steiner et al. (JAMA 2017) followed 750 women ages 30 to 44 with no history of infertility, trying to conceive naturally for up to 12 cycles. They tracked AMH, FSH, and inhibin B at baseline. The result: AMH levels did not predict cumulative pregnancy rates at 6 or 12 cycles.
Women with low AMH (under 0.7 ng/mL) had similar conception rates to women with higher AMH at the same age. Their take-home: in women without diagnosed infertility, AMH testing should not be used to guide reproductive timing.
This is the single most important finding to internalize. Low AMH at age 33 does not mean you will struggle to conceive naturally. High AMH does not guarantee easy conception. For natural fertility, age and whether ovulation is happening regularly matter much more.
AMH does not predict egg quality
AMH is a count, not a quality measure. Egg quality declines with maternal age — that is well established and measured by aneuploidy rates, miscarriage risk, and IVF success. But AMH does not capture quality. A woman with high AMH at age 42 still has age-42 egg quality. A woman with low AMH at age 28 still has the egg quality typical for 28.
AMH does not predict miscarriage risk
Cohort studies have not shown AMH to be a useful predictor of miscarriage in either natural or assisted conception cycles. Age and gestational milestones (see miscarriage rates by week) remain the dominant predictors.
AMH does not predict exact age of menopause
It correlates loosely with age at menopause, but the prediction interval is wide — often 5 years or more. A 30-year-old with low AMH cannot be confidently told she will reach menopause early. Some will; others will not.
What AMH does predict, and where it matters
IVF response
This is what AMH was originally validated for. In women undergoing IVF stimulation, AMH correlates strongly with:
- Number of antral follicles present at baseline.
- Number of eggs retrieved after stimulation.
- Risk of poor response (very few eggs) or hyperresponse (ovarian hyperstimulation syndrome).
This is genuinely useful for IVF planning. It guides the choice of stimulation protocol and gonadotropin dose. Iliodromiti et al. (Hum Reprod Update 2014), a meta-analysis of 30 studies, confirmed AMH as the best single biomarker for IVF response prediction.
Diminished ovarian reserve workup
In someone with unexplained infertility, irregular cycles, or a family history of early menopause, AMH plus antral follicle count helps confirm or exclude diminished ovarian reserve. This affects counseling and can shift treatment decisions toward earlier or more aggressive intervention.
PCOS workup
AMH is often elevated in PCOS (typically over 4.5 to 5 ng/mL, sometimes much higher), reflecting the larger pool of small antral follicles. International PCOS guidelines now include AMH as one acceptable substitute for ultrasound when evaluating polycystic ovary morphology. See our posts on PCOS Rotterdam criteria and PCOS and fertility.
Pre-treatment for cancer
Before chemotherapy or pelvic radiation, AMH helps quantify likely reproductive impact and informs fertility preservation decisions (egg or embryo freezing).
What to do with the result
A few common scenarios and reasonable interpretations:
Age 32, AMH 0.8 ng/mL, regular cycles, not currently trying: This is on the low end for age, but the Steiner et al. data suggest this does not predict inability to conceive naturally. If you want children eventually, the result is one input into when to try, alongside age and other factors. It is not a reason to panic, and it is not a reason to delay further than you would otherwise.
Age 38, AMH 1.5 ng/mL, trying for 6 months, regular cycles: At 38, ASRM recommends fertility evaluation after 6 months of trying. The AMH is in the typical range for age. The age itself is the bigger factor. Continue trying with appropriate timing — see the Ovulation Calculator and fertile window guide — and pursue evaluation if not pregnant by 12 months total.
Age 28, AMH 8.0 ng/mL, irregular cycles: The AMH is high, fitting a PCOS picture. Combined with irregular cycles, this would prompt a full PCOS workup including LH, free testosterone, fasting insulin, and pelvic ultrasound.
Age 41, AMH 0.3 ng/mL, considering IVF: Useful predictive information for IVF planning. Suggests a poor-responder protocol, modest egg yield expected, possibly counseling about donor options. Worth a reproductive endocrinology consultation.
Why AMH testing is overused for casual use
The pattern that has emerged: a 30-year-old with no fertility concerns gets an at-home AMH test out of curiosity. The result comes back at the lower end of normal. She becomes anxious, often makes life decisions (relationship, career, fertility preservation) based on a number that the 2017 JAMA paper says does not predict her natural fertility.
This is the scenario ASRM has cautioned against. AMH is a useful clinical test in the right context. It is not a useful screening test in the absence of clinical concern. The data simply do not support it as a predictor of natural conception in women who have not yet started trying.
Where AMH fits with other ovarian reserve tests
A complete ovarian reserve assessment usually includes:
- AMH (any cycle day).
- Day-3 FSH and estradiol (cycle days 2 to 4). High FSH suggests the pituitary is working harder to recruit a follicle, which in turn suggests reduced reserve.
- Antral follicle count by transvaginal ultrasound (any cycle day, often early follicular). Counts the small follicles directly.
In current practice, AMH plus antral follicle count is the most commonly used pair. They tend to correlate well and provide complementary information.
The bottom line
AMH is a useful test in the right hands and the right clinical context. It tells you about the size of the egg pool, predicts IVF response, and helps confirm diminished ovarian reserve or PCOS. It does not predict natural fertility, egg quality, miscarriage risk, or exact menopause timing.
If you are not having fertility concerns and have not started trying to conceive, an AMH test is unlikely to give you actionable information and may give you anxiety it does not warrant. If you are working through a fertility evaluation, planning IVF, or being assessed for PCOS, it is one of the more useful single numbers available. The skill is matching the right test to the right question — and for AMH, the right question is rarely “how fertile am I right now.”
The Period Calculator and Ovulation Calculator remain better starting points for trying-to-conceive timing in the average case. AMH is for specific clinical questions, not casual screening.