Short answer: a low AMH means your ovaries hold fewer eggs than average for your age, and that fewer eggs are likely to be collected if you have IVF. That is the whole of what it reliably tells you.
It is not a diagnosis of infertility. It does not predict whether you will conceive naturally. It says nothing about the quality of your eggs. It cannot tell you when you will reach the menopause. And it is not a reason for any clinic to refuse you treatment.
We are writing this because a low AMH result frightens more people than it helps, and a good deal of what is said about it online is either out of date or simply wrong.
There is no longer an official UK number, and that is not an oversight.
The previous NICE fertility guideline, CG156, published thresholds — an AMH at or below 5.4 pmol/L suggesting a likely low response to stimulation. NICE guideline NG257, which replaced it in March 2026, contains no numeric AMH threshold at all. Nor for antral follicle count, nor for FSH — and it now recommends against using FSH as a marker of ovarian reserve entirely, because “FSH levels do not predict clinical pregnancy or ovarian response”.
What you will get instead is your result read against an age-related range from the laboratory that ran it. In the UK results come in pmol/L; most international research uses ng/mL, where 1 ng/mL is roughly 7.14 pmol/L. Assays are not interchangeable between laboratories, so if you are having repeat tests, have them done in the same place.
The practical point: AMH falls steadily with age, so the same number means different things at 28 and at 42. A result of 6 pmol/L at 41 is unremarkable. At 27 it is a finding, and one worth looking into properly rather than filing.
One thing, and it does it well: how your ovaries will respond to the drugs used in IVF, and therefore roughly how many eggs might be collected.
That is genuinely useful. It shapes your stimulation protocol, it shapes how many cycles you should plan and budget for, and if you are freezing eggs it changes the whole arithmetic of how many cycles you need to bank a sensible number. NG257 endorses exactly this use: “Use AMH measurement or antral follicle count (AFC) as predictors of ovarian response to inform clinical decision making and patient counselling about the likelihood of live birth following assisted conception.”
NG257 is blunt: “Do not use anti-Müllerian hormone (AMH) measurement as a predictor of clinical pregnancy through spontaneous conception.”
Two studies are worth knowing about. The EAGER trial followed 1,202 women aged 18 to 40 with a history of pregnancy loss; those with AMH below 1 ng/mL (about 7 pmol/L) had similar cumulative pregnancy rates to women with normal values. The Time to Conceive study followed 750 women aged 30 to 44 with no known fertility problems; those with AMH below 0.7 ng/mL (about 5 pmol/L) had similar cumulative pregnancy rates after both six and twelve cycles of trying.
To be fair to the science, it is not literally no relationship — a large 2024 study of 3,150 women found AMH below 1 ng/mL was associated with a modest reduction in the chance of natural conception. But a modest population-level association is a different thing from a prediction about you.
This is the part that matters most, and the American Society for Reproductive Medicine states it plainly. Markers of ovarian reserve are “good predictors of oocyte yield, but poor independent predictors of reproductive potential. Therefore, they should not be used as a fertility test or to deny access to infertility treatment.” And: “AMH as an independent variable is only weakly predictive of pregnancy at best.”
Their conclusion on the wider question is worth committing to memory: “Age is a much stronger predictor of reproductive success than is ovarian reserve.”
AMH counts follicles. It does not grade them. There is no blood test for egg quality and any clinic implying otherwise is overselling. Age remains the best available guide. You can have a low AMH and good eggs, and a reassuring AMH and eggs that fertilise poorly.
A 2023 systematic review in Human Reproduction Update, pooling 41 studies and 28,858 women, found that “AMH alone could not be used to predict age at menopause with precision”, with estimates and confidence intervals “ranging from 2 to 12 years for women aged under 40”. A twelve-year window is not a prediction.
People with a very low result deserve real figures rather than reassurance, so here they are.
An analysis of more than 5,000 IVF cycles in American national registry data, in women whose AMH was below 0.16 ng/mL — roughly 1.1 pmol/L, which is about as low as the test goes — found that 54% of cycles were cancelled, half produced three eggs or fewer, and a quarter reached no embryo transfer. The live birth rate was 9.5% per cycle started, and 20.5% per embryo transfer.
Those are hard numbers, and we would rather you had them than a vague answer. But read the conclusion the same authors drew: extremely low AMH values “may be used to appropriately counsel women regarding suboptimal response and yield, but should not be used to refuse treatment”.
One in five transfers at the absolute floor of the test is not nothing.
Less than you might expect, and this one surprises people.
A 2024 Cochrane review of 26 randomised trials and 8,520 women looked at whether tailoring the dose of stimulation drugs to ovarian reserve markers improves outcomes. Its conclusion: “current evidence does not provide a clear justification for adjusting the dose of 150 IU in poor or normal responders, especially as increased dose is associated with greater total FSH dose and cost.”
Where individualised dosing did help was the opposite end — reducing the risk of ovarian hyperstimulation in high responders. So if you have been told a low AMH means you need a much bigger dose of drugs, ask why. More medication does not reliably produce more eggs from ovaries that hold fewer, and it certainly costs more.
What a low AMH should change is the plan: realistic expectations about egg numbers per cycle, a frank conversation about how many cycles that might mean, and a sense of urgency about age, because age is the variable that is actually moving.
Here is the exception to all the reassurance above, and it matters.
A very low AMH in a young woman is a genuine clinical signal. The same 2023 review that dismissed AMH as a menopause predictor also found that “the finding of very low AMH values in young women is both of clinical value in indicating an increased risk of developing POI and may facilitate timely diagnosis” — POI being premature ovarian insufficiency.
POI is defined by the 2024 international guideline as “loss of ovarian activity before the age of 40 years”, and it is more common than most people assume: prevalence estimates have risen from around 1% in older studies to 3.5% in recent ones. Loss of ovarian function between 40 and 44 is termed early menopause.
Important: AMH is not how POI is diagnosed. The guideline is explicit — “anti-Müllerian hormone (AMH) should not be used as the primary diagnostic test for POI”. Diagnosis needs irregular cycles or absent periods for at least four months plus an FSH above 25 IU/L, repeated after four to six weeks if there is any doubt.
So if your AMH is very low and you are under 35 — and particularly if your periods are irregular or absent, or there is a family history of early menopause — that is a reason to be properly assessed, not a reason to panic and not a reason to be told it is fine. Untreated POI carries real consequences for bone density and cardiovascular health, quite separately from fertility, which is why getting the diagnosis right and early matters.
Often nothing identifiable, and the international POI guideline says so directly — clinicians should tell women “that an exact cause may not be identified”. Where a cause is found, the evidence is strongest for:
And three reasons a result can look artificially low that have nothing to do with your ovaries: hormonal contraception can suppress AMH while you are taking it, AMH is lower at higher BMI, and it varies somewhat across the cycle.
One thing we will not tell you, because we cannot support it: that smoking lowers your AMH. It is often stated as fact. The international POI guideline lists smoking among modifiable risk factors, but only as expert opinion, and the best-quality study we could find — a prospective study using biochemically verified smoking status — found no significant difference in AMH or antral follicle count between current smokers, ex-smokers and never-smokers. There are excellent reasons to stop smoking before fertility treatment. A higher AMH is not reliably one of them.
No. There is no supplement, diet or treatment shown to increase the number of eggs your ovaries hold. Anything sold on that promise is not supported by evidence, and we would rather say so than take your money for it.
What you can change is the timeline. If your reserve is genuinely low for your age, the useful response is to act sooner rather than to spend six months on supplements.
Your AMH is read alongside an ultrasound of your ovaries, your age and your history — never alone, and never over email. Every result is reviewed by a Fertility Doctor before you are told anything.
It has one direct practical consequence here: AMH above 10 pmol/L is one of the criteria for our Simple IVF™ pathway at £2,900 a cycle. If your result is below that, it means the more thorough Conventional IVF pathway from £4,500 is the right route — not that treatment is off the table. All the criteria are published on our prices page.
A female fertility assessment, which includes AMH alongside a scan and a consultation, is £390.
No. It describes how many eggs are likely to be collected in a stimulated cycle. Plenty of women with a low AMH conceive, including without treatment.
You should be seen, which is different from being worried. A very low AMH in a young woman warrants proper assessment — FSH testing, a scan, and consideration of the genetic and autoimmune causes above — rather than either reassurance or alarm.
Possibly, and sooner rather than later if so, but go in with clear eyes: a low AMH means fewer eggs per cycle, so it may take more cycles to bank a useful number, and the cost arithmetic changes. We will give you a realistic figure for your own situation before you commit to anything.
Yes, gradually, as it does for everyone with age. The rate varies and a single result cannot tell you your trajectory. Repeat testing is generally only useful if it will change a decision.
Not automatically. It depends on your age, whether your tubes are open, your partner’s semen analysis and how long you have been trying. Where time is genuinely short, going straight to IVF can be the right call — and we will say so.
Usually, yes. Donor eggs become a conversation worth having when repeated cycles have produced very few or poor-quality embryos, or where the numbers make your own chance very low — and it is a conversation we will start honestly rather than after you have paid for several more cycles.
If you have a low AMH result and nobody has explained it to you properly, bring it in. Start with a free 15-minute consultation with a Fertility Specialist — no referral needed, no obligation. Book a free consultation, read more about what an AMH test measures, or see our fertility assessments.
