Guide to Anti-Müllerian Hormone (AMH)

WRITTEN BY

The Levels Team

Updated: 05/22/2025|12 min read

Summary

Anti-Müllerian Hormone (AMH) is a biomarker for a woman's ovarian reserve, which is the number of follicles (immature eggs) left in the ovaries.

Why It Matters

In women of reproductive age, anti-Müllerian hormones (AMH) are produced in granulosa cells in the ovaries. Your eggs sit in structures called follicles, and the smaller, developing follicles produce AMH. Women are born with about 1-2 million eggs (oocytes), but this number steadily drops throughout life until menopause, when the supply runs out.

Higher AMH generally means having more eggs in reserve and better chances for pregnancy, while lower levels might signal fewer eggs and potentially more difficulty conceiving. However, AMH doesn't indicate egg quality, which can also affect fertility.

AMH testing helps your doctor estimate how much reproductive time you might have. For women undergoing fertility treatments, AMH levels help predict how your ovaries will respond to the medications used to stimulate egg production.

AMH can also help identify conditions like polycystic ovary syndrome (PCOS), where levels tend to be high because of the many small follicles in the ovaries. Changes in AMH can flag other health issues, including certain ovarian tumors, damage to the ovaries from chemotherapy or radiation, and primary ovarian insufficiency (POI)---also called premature ovarian failure---which is when ovaries stop working properly before age 40.

Associated Symptoms

AMH levels themselves are laboratory findings rather than medical conditions. However, abnormal levels may be associated with certain reproductive health conditions, each with its own symptoms.

Conditions potentially associated with low AMH levels:

• Diminished ovarian reserve: Difficulty conceiving naturally, potentially poor response to fertility medications
• POI: Irregular or skipped periods, hot flashes, night sweats, vaginal dryness, and other menopause-like symptoms before age 40
• Ovarian damage: From surgery, chemotherapy, or radiation, which may lead to similar symptoms as diminished ovarian reserve

Conditions potentially associated with high AMH levels:

• PCOS: Irregular menstrual cycles, excess hair growth (hirsutism), acne, weight management difficulties, and insulin resistance
• Certain ovarian tumors: Particularly granulosa cell tumors, which may cause menstrual irregularities, pelvic pain, or abdominal swelling
• Normal variation in young women: Typically asymptomatic

AMH is just one marker of reproductive health, and levels should be interpreted alongside other hormonal tests, ultrasound findings, and clinical symptoms. AMH testing is most valuable when used as part of a comprehensive fertility assessment rather than in isolation.

Clinical Ranges

Female:

• 18-25 years: 1.02-14.63 ng/mL
• 26-30 years: 0.69-13.39 ng/mL
• 31-35 years: 0.36-10.07 ng/mL
• 36-40 years: 0.18-5.68 ng/mL
• 41-45 years: 0.01-2.99 ng/mL
• > 45 years: Not established

Lifestyle Factors That Can Impact It

Activities that may affect AMH include:

• Body weight: Both obesity and being very underweight can negatively impact AMH levels. Fat cells produce estrogen, which can disrupt normal hormone balance, while severe caloric restriction can suppress reproductive hormone production.
• Smoking: Smoking may lower AMH levels, potentially accelerating the loss of follicles and leading to earlier menopause.
• Diet and nutrition: Some research suggests that diets rich in antioxidants, vitamin D, and omega-3 fatty acids may support healthy AMH levels, while diets high in processed foods and trans fats may negatively affect reproductive hormones.
• Physical activity: Moderate exercise can help maintain healthy AMH levels, particularly in women with PCOS. However, excessive, intense exercise may potentially lower AMH levels in some women.
• Stress management: Chronic stress can disrupt hormone balance through elevated cortisol levels, potentially affecting AMH production.

Other Factors That Can Impact It

Medical Conditions

• PCOS: PCOS causes hormonal imbalances that prevent follicles from developing properly, resulting in multiple small follicles that produce excess AMH.
• POI: This condition causes a loss of ovarian function before age 40 and shows significantly decreased AMH levels.
• Endometriosis: This occurs when tissue that is similar to the lining of the uterus grows in other areas of the body. The condition can negatively impact ovarian function and may cause lower AMH levels.
• Autoimmune disorders: Conditions like thyroid disorders, lupus, and rheumatoid arthritis may affect ovarian function and AMH production.
• Ovarian tumors: Certain ovarian tumors, particularly granulosa cell tumors, can produce abnormal amounts of AMH.

Medications and Supplements

• Hormonal contraceptives
• Chemotherapy and radiation
• GnRH agonists/antagonists
• DHEA supplements

Individual Factors

• Age: AMH peaks in the early 20s and steadily declines until becoming undetectable around menopause.
• Pregnancy and postpartum: AMH levels typically decrease during pregnancy and may take several months postpartum to return to baseline.
• Timing of puberty: Earlier onset of puberty may be associated with different AMH trajectories throughout reproductive life.
• Previous ovarian surgery: Procedures like ovarian cystectomy can potentially reduce follicular count and lower AMH levels.

Testing Accuracy and Stability

AMH testing is generally reliable, but results should be interpreted alongside other factors.

Factors That Can Affect the Accuracy of Your Test

• Recent ovarian surgery (within 3 months)
• Active hormonal medication use, especially GnRH agonists
• Severe vitamin D deficiency may affect AMH production
• Acute illness or significant physical stress
• Recent chemotherapy

How It Relates to Other Markers

Other tests can provide your doctor insights about your health status when they're viewed alongside AMH results. These tests may include:

• Follicle stimulating hormone (FSH) and estradiol: These hormones are often measured on day 3 of the menstrual cycle to help evaluate pituitary-ovarian communication.
• Testosterone: Testosterone and AMH may be elevated in people with PCOS.
• Antral follicle count (AFC): This is an ultrasound test that counts visible follicles at the beginning of the menstrual cycle.
• Luteinizing hormone (LH): Helps diagnose PCOS. An elevated LH:FSH ratio often accompanies high AMH levels in people with PCOS.
• Thyroid function tests: Thyroid disorders can impact fertility independent of ovarian reserve and may sometimes affect AMH levels.
• Prolactin: Elevated prolactin can suppress ovarian function and cause menstrual irregularities that might be confused with diminished ovarian reserve.
• Comprehensive metabolic panel: Assesses overall health and confirms or rules out conditions like insulin resistance or diabetes that might affect reproductive function.

How Results Could Relate to Other Marker Values

• Low AMH + high FSH + low AFC: This combination could suggest diminished ovarian reserve.
• High AMH + high LH + high testosterone: May suggest PCOS.
• Low AMH + normal estradiol: Might indicate fewer follicles but normal follicular function, suggesting that while fewer eggs might be retrieved, their quality could be adequate.
• Low AMH + low estradiol: May suggest low ovarian reserve.

Follow-up Considerations

You should always talk to your doctor if you have medical concerns or questions.

When Re-Testing May be Appropriate

• Annual testing for women with low or borderline low AMH levels
• 3-6 months after stopping hormonal contraceptives if baseline was taken while on hormonal birth control
• Before initiating each IVF cycle to adjust medication protocols
• 3-6 months following ovarian surgery to assess impact on ovarian reserve
• Before and after cancer treatments to evaluate fertility preservation options

Additional Testing Your Doctor May Consider

• Genetic testing for women with low AMH for their age (FMR1 premutation, other ovarian insufficiency genes)
• Transvaginal ultrasound for assessment of ovarian structure
• Detailed insulin resistance and androgen assessment when PCOS is suspected
• Anti-ovarian antibody testing when autoimmune causes of diminished reserve are suspected

When Additional Care May be Warranted

• Women under 35 with AMH levels below 1.0 ng/mL
• Elevated AMH in conjunction with a pelvic mass
• Any rapid decline in AMH levels
• Infertility lasting 6 or more months with low or high AMH levels
• Combination of low AMH and irregular menstrual cycles
• Fertility concerns
• Symptoms of early perimenopause/menopause
• Symptoms of PCOS that impact quality of life

Bibliography