AMH test: what does it tell you about ovarian reserve?

The AMH test (anti-Müllerian hormone) is a blood test used to assess ovarian reserve — an indirect measure of the remaining egg supply in the ovaries. Anti-Müllerian hormone is produced by granulosa cells in ovarian follicles, and its blood level correlates with the number of small antral follicles available for recruitment. This is why the test is widely known as an AMH fertility test and plays a central role in reproductive endocrinology.

Unlike FSH or estradiol, AMH levels remain relatively stable throughout the menstrual cycle, so the test can be performed on any cycle day. AMH declines naturally with age and approaches zero at menopause. Both low and high values provide critical information for fertility planning, determining IVF stimulation protocols, and evaluating conditions such as polycystic ovary syndrome (PCOS).

In this guide you will learn about the AMH normal range, AMH levels by age, the meaning of low AMH or elevated AMH, and when you should consult a specialist about your results.

AMH levels show a physiological decline that mirrors the gradual depletion of the ovarian follicle pool. Ovarian reserve is at its peak at birth; from puberty onward the pool steadily shrinks, and the decline accelerates notably after age 35. The table below summarises typical AMH levels by age.

These figures are general reference values; slight differences may exist between laboratories. Always compare your result with the reference range printed on your own report. Values below 1.0 ng/mL are generally considered indicative of low ovarian reserve, while values above 3.5 ng/mL may warrant evaluation for PCOS.

For patients planning IVF, the AMH level helps guide gonadotropin dosing and predict the expected oocyte yield. A low AMH result does not mean pregnancy is impossible; however, it provides valuable data for timing and individualising treatment strategy.

Low AMH can be associated with a variety of clinical scenarios. The most common causes include:

• Age-related decline in ovarian reserve: The most frequent cause; follicle loss accelerates after age 35.
• Ovarian surgery: Excision of endometriomas or ovarian cyst removal can reduce healthy tissue and lower AMH.
• Autoimmune oophoritis: The immune system attacking ovarian tissue leads to premature follicle depletion.
• Chemotherapy / radiotherapy: Gonadotoxic treatments can permanently shrink the follicle pool.
• Genetic factors: Fragile X premutation or Turner syndrome mosaicism may contribute to premature ovarian insufficiency.
• Smoking: Chronic tobacco use is a well-established risk factor that accelerates ovarian ageing.

High AMH is most commonly associated with polycystic ovary syndrome (PCOS). In PCOS the ovaries contain an excess of small antral follicles, each producing AMH, which drives the total level upward. Elevated AMH is also considered during pre-IVF assessment as a risk factor for ovarian hyperstimulation syndrome (OHSS).

When interpreting AMH, a single value may not be sufficient. Antral follicle count (AFC) on ultrasound, FSH, estradiol, and clinical history should all be evaluated together for a comprehensive picture.

Consider consulting a reproductive endocrinologist or gynaecologist in the following situations:

• You are over 35 and have been trying to conceive for six months without success (one year if under 35)
• Your AMH result is low for your age and you are planning a pregnancy
• You experience irregular cycles, suspected anovulation, or symptoms of PCOS
• You want to explore fertility preservation options before chemotherapy or ovarian surgery
• You are planning IVF or other assisted reproductive techniques

Your doctor will typically order an AMH fertility test alongside an ultrasound for antral follicle count, FSH, LH, estradiol, and — if indicated — genetic testing, to build a complete ovarian reserve profile. A low AMH alone does not equal infertility; it is a guide for timing and personalising your treatment plan.

This content is for informational purposes only and does not replace medical diagnosis or treatment. Always discuss your test results with a qualified healthcare professional.