AMH (Anti-Mullerian Hormone) Blood Test: Normal Ranges, Causes & What Your Results Mean

What Is Anti-Mullerian Hormone (AMH)?

Anti-Mullerian hormone (AMH) is a glycoprotein hormone produced by the granulosa cells of small growing follicles in the ovaries. It serves as the most reliable blood marker of a woman's ovarian reserve - the quantity of remaining eggs. Unlike most reproductive hormones, AMH levels remain relatively stable throughout the menstrual cycle, making it convenient to test at any time without the need to time the blood draw to a specific cycle day.

In the developing foetus, AMH plays a important role in sexual differentiation. In males, AMH is produced by Sertoli cells in the testes and causes the regression of Mullerian ducts (which would otherwise develop into the uterus, fallopian tubes, and upper vagina). This is how the hormone got its name. In adult women, AMH's primary clinical significance lies in its role as a fertility marker.

AMH is produced by pre-antral and small antral follicles - the pool of follicles that are "next in line" for potential ovulation. As a woman's egg reserve naturally declines with age, AMH levels fall accordingly. By the time of menopause, AMH becomes undetectable. This makes it an invaluable tool for assessing reproductive potential, guiding fertility treatment, and diagnosing certain ovarian conditions.

Why Is AMH Tested?

AMH testing has become a standard part of fertility assessment and is also used in several other clinical contexts:

• Assessing ovarian reserve: The primary use. Women considering delaying pregnancy, those with a family history of early menopause, or anyone wanting to understand their reproductive timeline may benefit from AMH testing.
• Predicting IVF response: AMH is the single best predictor of ovarian response to stimulation during IVF. Women with higher AMH produce more eggs, while those with very low AMH may respond poorly. This helps fertility specialists tailor medication dosing.
• Diagnosing polycystic ovary syndrome (PCOS): AMH is typically elevated 2–3 fold in PCOS due to the increased number of small antral follicles. It is increasingly used as a diagnostic criterion alongside ultrasound and hormonal profiles.
• Predicting menopause timing: AMH decline follows a predictable trajectory. Very low AMH in a young woman may suggest premature ovarian insufficiency (POI) and an earlier-than-expected menopause.
• Monitoring gonadotoxic treatment: Chemotherapy and radiotherapy can damage the ovaries. AMH testing before and after treatment helps assess the impact on fertility.
• Evaluating granulosa cell tumours: Rare ovarian tumours that produce AMH, causing elevated levels that serve as a tumour marker.
• Paediatric use: In boys, AMH helps assess testicular function and can aid in the diagnosis of disorders of sexual development (DSD).

Normal AMH Ranges

AMH is measured in picomoles per litre (pmol/L) in the UK, though some international references use nanograms per millilitre (ng/mL). The conversion factor is: 1 ng/mL = 7.14 pmol/L.

Category	AMH Level (pmol/L)	AMH Level (ng/mL)	Interpretation
High (possible PCOS)	Greater than 48.5 pmol/L	Greater than 6.8 ng/mL	May indicate PCOS
Optimal	21.98–48.5 pmol/L	3.08–6.8 ng/mL	Good ovarian reserve
Satisfactory	10.18–21.97 pmol/L	1.42–3.07 ng/mL	Adequate reserve, reasonable IVF response expected
Low	3.08–10.17 pmol/L	0.43–1.42 ng/mL	Reduced reserve, may respond poorly to IVF stimulation
Very low	Less than 3.08 pmol/L	Less than 0.43 ng/mL	Very low reserve, poor IVF prognosis

It is essential to interpret AMH in the context of age. An AMH of 15 pmol/L is normal for a 38-year-old but would be concerning in a 25-year-old. Age-specific reference ranges provide more meaningful interpretation:

Age	Median AMH (pmol/L)	Expected Range (pmol/L)
25 years	28.0	14.0–56.0
30 years	20.0	10.0–40.0
35 years	14.0	5.0–28.0
38 years	10.0	3.0–20.0
40 years	7.0	1.5–15.0
43 years	3.5	0.5–8.0
45+ years	1.5	0.1–5.0

What Do High AMH Levels Mean?

Elevated AMH is most commonly associated with polycystic ovary syndrome (PCOS) and generally reflects a high number of small antral follicles in the ovaries.

Conditions associated with high AMH

• Polycystic ovary syndrome (PCOS): AMH levels in PCOS are typically 2–4 times higher than in age-matched controls. The elevated AMH reflects the increased follicle count and also contributes to the anovulatory cycle by inhibiting follicle progression to ovulation.
• Granulosa cell tumours: These rare ovarian tumours produce AMH, and it serves as a useful tumour marker for diagnosis and monitoring after treatment.
• Good ovarian reserve: In the context of fertility assessment, high AMH (without PCOS features) indicates a large egg reserve and usually predicts an excellent response to IVF stimulation - though it also increases the risk of ovarian hyperstimulation syndrome (OHSS).

Symptoms associated with high AMH (PCOS-related)

• Irregular or absent periods
• Excess facial or body hair (hirsutism)
• Acne
• Weight gain, particularly around the abdomen
• Difficulty conceiving
• Thinning hair on the scalp

What Do Low AMH Levels Mean?

Low AMH indicates a diminished ovarian reserve - fewer eggs remaining than expected for your age. This is the finding that causes the most anxiety, but it requires careful interpretation.

Key points about low AMH

• Low AMH does not mean infertility: Women with low AMH can and do conceive naturally. AMH reflects egg quantity, not egg quality. A 30-year-old with low AMH still has younger, healthier eggs than a 40-year-old with normal AMH.
• Low AMH does predict poor IVF response: Fewer eggs are typically retrieved during IVF stimulation, which reduces the number of embryos available and the cumulative success rate per cycle.
• Low AMH may suggest earlier menopause: If AMH is very low for your age, you may reach menopause earlier than average. The average age of menopause in the UK is 51.

Causes of low AMH

• Normal ageing: The most common reason. AMH naturally declines from the mid-20s onward.
• Premature ovarian insufficiency (POI): Defined as loss of ovarian function before age 40. Affects approximately 1% of women.
• Endometriosis: Ovarian endometriomas (chocolate cysts) and their surgical removal can damage ovarian tissue and reduce AMH.
• Ovarian surgery: Any surgery involving the ovaries (cyst removal, oophorectomy) reduces the follicle pool.
• Chemotherapy and radiotherapy: Gonadotoxic treatments can cause significant, sometimes permanent, damage to the ovarian reserve.
• Smoking: Smoking accelerates ovarian ageing and is associated with lower AMH levels.
• Autoimmune conditions: Thyroid autoimmunity and adrenal autoimmunity have been linked to reduced ovarian reserve.
• Genetic factors: Some women inherit a smaller initial follicle pool or faster rate of follicle loss.

How to Support Your Ovarian Health

While you cannot significantly increase your ovarian reserve (the number of eggs is largely determined by genetics and age), you can take steps to protect the eggs you have and optimise your reproductive health:

Lifestyle factors

• Stop smoking: Smoking accelerates ovarian ageing by an estimated 1–4 years. Quitting is the single most impactful lifestyle change for preserving fertility.
• Maintain a healthy BMI: Both obesity and being underweight can impair ovarian function. A BMI of 19–25 is associated with optimal fertility.
• Exercise moderately: Regular moderate exercise supports hormonal balance. However, excessive high-intensity exercise can disrupt ovulation.
• Reduce stress: Chronic stress affects the hypothalamic-pituitary-ovarian axis, potentially disrupting ovulation and cycle regularity.
• Limit alcohol: Heavy alcohol consumption has been associated with reduced AMH levels in some studies. Moderate intake (within NHS guidelines) is unlikely to cause harm.

Nutritional support

• Vitamin D: Several studies have found a positive correlation between vitamin D levels and AMH. Ensure adequate supplementation, especially during winter months (the NHS recommends 10 µg/day for all UK adults).
• Coenzyme Q10 (CoQ10): Research suggests CoQ10 may improve egg quality (though not quantity) by supporting mitochondrial function in oocytes. Doses of 200–600 mg/day are commonly used in fertility practice.
• DHEA: Dehydroepiandrosterone supplementation has been studied in women with diminished ovarian reserve undergoing IVF, with some evidence of improved outcomes. This should only be used under medical supervision.
• Antioxidant-rich diet: Fruits, vegetables, nuts, and oily fish provide antioxidants that may protect eggs from oxidative damage.
• Folic acid: Essential for all women of reproductive age (400 µg/day), regardless of AMH level.

Medical options

• Egg freezing: If AMH is declining and you are not ready for pregnancy, egg freezing preserves your current egg quality for future use.
• Fertility treatment: IVF with tailored stimulation protocols can still achieve pregnancy even with low AMH, though success rates are reduced.
• Referral to a fertility specialist: If your AMH is low for your age, a timely referral ensures you have the full picture and can make informed decisions.

When Should You Get Tested?

Consider having your AMH tested if:

• You are over 30 and considering delaying pregnancy
• You have a family history of early menopause or premature ovarian insufficiency
• You are planning to freeze your eggs or start IVF
• You have irregular periods or suspected PCOS
• You have had ovarian surgery, chemotherapy, or radiotherapy
• You have endometriosis
• You are a smoker and concerned about fertility
• You simply want to understand your reproductive timeline

AMH can be tested at any point in your menstrual cycle - no special timing is needed. The test requires a simple blood draw. For routine fertility awareness, testing once is often sufficient, though repeat testing every 1–2 years may be useful for tracking changes over time.

Which Lola Health Tests Include AMH?

AMH is available in Lola Health's hormone and fertility panels:

• Peak Insights (70 Biomarkers) - Our most comprehensive panel, including AMH alongside thyroid, metabolic, and nutritional markers.
• Female Hormone Blood Test - Focused panel for assessing reproductive and hormonal health.

All Lola Health tests use a venous blood draw at one of our nationwide partner clinics — never a finger prick. Results are reviewed by a doctor and returned within 4 working days.