Anti-Müllerian Hormone (AMH): Ovarian Reserve and What It Cannot Predict

AMH is a hormone made by granulosa cells in small ovarian follicles. As the follicle pool changes with age, AMH usually changes too. This makes AMH a marker related to follicle quantity, not a direct count of eggs and not a direct test of whether an egg can produce a healthy pregnancy.^{See reference 1,See reference 2}

AMH is often measured with an ovarian ultrasound measure called antral follicle count. Together, these tests can help estimate how many oocytes may be obtained after controlled ovarian stimulation. They are much less informative about reproductive potential than many people assume when age and the broader fertility assessment are left out.^{See reference 2}

AMH can be measured at several points in a menstrual cycle, but it is not perfectly stable. The assay platform, calibration, sample timing, hormonal contraception and the population used to establish an interval can all affect the result. A number copied without the laboratory details is incomplete.^{See reference 2,See reference 3}

AMH is commonly reported in ng/mL or pmol/L. These are different units, and the numerical value cannot be compared directly between them. Because assays also differ, an online conversion or borrowed cut-off can create false precision. This guide therefore does not provide a conversion or a universal normal range.^{See reference 2,See reference 3}

Keep the original value, unit, laboratory reference interval, assay or method if shown, collection date, age and relevant contraception or treatment context. If a result is near a laboratory boundary or does not fit the clinical question, ask the ordering clinician or laboratory how it should be interpreted rather than recalculating it from a different source.^{See reference 1,See reference 2,See reference 3}

AMH is a blood test and usually needs no special preparation. The next step depends on why it was ordered. In fertility care, a clinician may combine it with age, history, antral follicle count, ovulation information and semen or tubal assessment. In a PCOS assessment, it is only one possible component of a broader diagnostic framework.^{See reference 1,See reference 2,See reference 4}

A very low result should not be treated as proof that pregnancy cannot occur or as a reason to refuse fertility treatment. A higher result can be associated with a greater response to stimulation, but it does not make egg quality or pregnancy outcomes predictable. A clinician can explain what the value changes in the specific decision being made.^{See reference 1,See reference 2}

AMH should not be used as a stand-alone primary diagnostic test for premature ovarian insufficiency. When that condition is considered, symptoms, menstrual history, follicle-stimulating hormone and the wider clinical context are important.^{See reference 5}