The anti-Müllerian hormone (AMH) is a crucial biomarker in the evaluation of ovarian reserve and female fertility. Produced by granulosa cells in small ovarian follicles, AMH provides valuable information about the number of remaining eggs. AMH levels tend to naturally decrease with age, reflecting the gradual reduction of ovarian reserve.
At a glance
| AMH is a reliable indicator of ovarian reserve, but it does not accurately predict egg quality nor guarantee reproductive success. |
| Normal AMH levels vary by age, progressively decreasing from adolescence to menopause. |
| AMH tests are useful for personalizing fertility treatments, but they must be interpreted alongside other reproductive factors. |
Definition and Function of the AMH Hormone
The anti-Müllerian hormone (AMH) is a glycoprotein produced by granulosa cells in developing ovarian follicles that serves as an indicator of ovarian reserve, representing the number of remaining eggs in a woman's ovaries.
AMH belongs to the transforming growth factor beta (TGF-β) family and plays multiple roles in reproductive development. During male fetal development, AMH causes the regression of the Müllerian ducts, structures that would otherwise form the uterus and fallopian tubes. In women, AMH is produced after birth by growing ovarian follicles.
A fundamental aspect of AMH is its relationship with ovarian reserve. Primordial follicles, which contain immature eggs, begin to develop and produce AMH when they reach the preantral and early antral stages. Therefore, serum AMH levels reflect the population of these growing follicles, providing an indirect assessment of ovarian reserve.
According to Dr. María González, a reproductive medicine specialist: "AMH is one of the most reliable markers we currently have to assess ovarian reserve. Unlike other hormones like FSH, AMH levels remain relatively constant throughout the menstrual cycle, making it easier to measure at any time" (González, 2023).
It is important to understand that AMH does not measure egg quality, but rather quantity. The number of primordial follicles decreases with age, which explains the progressive reduction of AMH levels from adolescence to menopause. This decrease is not linear and can vary significantly among women of the same age, revealing the individuality of reproductive patterns.
Factors influencing AMH levels include genetics, ethnicity, and certain medical conditions. Women with polycystic ovary syndrome (PCOS) often present elevated AMH levels due to the higher number of antral follicles. Conversely, treatments such as chemotherapy, ovarian surgery, or pelvic radiation can reduce AMH levels by affecting ovarian reserve.
AMH Levels and Their Significance
Reference values for AMH vary by age and the laboratory performing the test. Generally, levels are expressed in nanograms per milliliter (ng/ml) or picomoles per liter (pmol/l). The interpretation of results should always consider the woman's age, as what is considered "normal" changes significantly throughout the reproductive lifespan.
As a general guideline, we can consider that in women of reproductive age (25-35 years):
- High levels (>3.0 ng/ml): May indicate good ovarian reserve or conditions such as polycystic ovary syndrome
- Normal levels (1.0-3.0 ng/ml): Suggest adequate ovarian reserve for age
- Low levels (0.5-1.0 ng/ml): May indicate diminished ovarian reserve
- Very low levels (<0.5 ng/ml): Suggest significantly reduced ovarian reserve
Elevated AMH levels are often associated with a greater response to medications used in in vitro fertilization (IVF) treatments, which can result in a higher number of retrieved eggs. However, excessively high levels may indicate conditions such as polycystic ovary syndrome (PCOS), which could complicate fertility treatments.
In a study published in the Journal of Clinical Endocrinology & Metabolism, researchers found that "women with AMH levels below 0.5 ng/ml had significantly lower chances of achieving pregnancy through IVF compared to those with levels above 1.0 ng/ml" (Chen et al., 2022). Nevertheless, it is crucial to understand that low AMH levels do not preclude natural pregnancy or assisted reproductive techniques.
Limitations of AMH Interpretation
Although valuable, AMH has limitations as a predictor of fertility. The American Society for Reproductive Medicine (ASRM) emphasizes that AMH does not predict the ability to conceive naturally nor guarantee success in assisted reproductive treatments. Women with low AMH may conceive naturally, while others with high levels may experience difficulties due to factors such as egg quality or uterine issues.
Age remains the most determining factor in female fertility. A young woman with low AMH levels will generally have a better reproductive prognosis than an older woman with similar or even higher levels, due to the better egg quality associated with youth.
It is important to consider AMH in the context of other relevant fertility factors, such as menstrual cycle regularity, fallopian tube health, ovulatory function, and male factors. A comprehensive fertility evaluation requires a holistic approach that considers these multiple aspects.
Diagnosis and AMH Testing
Measuring AMH levels is done through a simple blood test that can be performed at any time during the menstrual cycle, a significant advantage over other hormonal tests like FSH, which must be done on specific days. This flexibility makes the AMH test convenient for both doctors and patients.
The procedure for the AMH test is straightforward:
- A venous blood sample is drawn, usually from the arm
- The sample is analyzed in the laboratory using enzyme-linked immunosorbent assay (ELISA) or other immunoassay methods
- Results are usually available within a few days
It is advisable that the interpretation of results be performed by a reproductive medicine specialist, who will consider the value in the context of age, symptoms, other hormonal parameters, and the patient's reproductive goals.
The AMH test is often complemented by an antral follicle count (AFC) via transvaginal ultrasound. This visual examination allows counting the developing follicles in both ovaries, providing another measure of ovarian reserve that correlates well with AMH levels. The combination of both tests offers a more comprehensive and reliable assessment.
In addition to AMH and AFC, a complete fertility evaluation may include:
- Measurement of other reproductive hormones (FSH, LH, estradiol, progesterone)
- Assessment of fallopian tube patency
- Examination of the uterine cavity
- Semen analysis in the male partner
In recent years, commercial kits have emerged that allow for at-home AMH testing. However, specialists recommend caution with these options, as accuracy may vary and professional interpretation remains essential to adequately contextualize the results.
Implications for Fertility Treatment
AMH levels significantly influence the approach to fertility treatments. This information allows specialists to personalize protocols and set realistic expectations, tailoring interventions to each woman's specific ovarian reserve.
Personalization of Stimulation Protocols
In treatments such as in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI), AMH helps determine the optimal dose of gonadotropins for ovarian stimulation. Women with high AMH generally require lower doses to avoid ovarian hyperstimulation, while those with low AMH may need higher doses to achieve an adequate response.
Dr. Javier Rodríguez, director of the Assisted Reproduction Unit at La Paz University Hospital, states: "AMH is an indispensable tool for personalizing stimulation protocols. It allows us to adjust medication doses more precisely, minimizing risks and optimizing outcomes" (Rodríguez, 2023).
For women with very low AMH, specialists may recommend strategies such as:
- Gentle or minimal stimulation protocols
- Egg accumulation through multiple stimulation cycles
- Early consideration of donor egg options
Fertility Preservation
AMH levels are especially relevant in decisions regarding fertility preservation. Women who wish to postpone motherhood can use this information to make informed decisions about the optimal timing for egg freezing.
Knowing a low AMH may motivate consideration of preservation earlier, while normal or high levels may provide some reassurance, though never absolute guarantees. It is important to remember that AMH indicates quantity, not quality, and that the latter inevitably decreases with age, regardless of AMH levels.
For cancer patients facing potentially gonadotoxic treatments such as chemotherapy or pelvic radiation, measuring AMH before and after treatment can help assess the impact on ovarian reserve and guide future reproductive options.
Genetic Counseling and Alternative Options
In cases of extremely low or undetectable AMH, especially in young women, it may be advisable to conduct genetic evaluations to rule out conditions such as primary ovarian insufficiency. These patients may benefit from specialized genetic counseling to understand the implications and consider options such as egg donation or adoption.
It is essential to highlight that low AMH levels do not mean an impossibility to conceive. Many women with diminished ovarian reserve achieve pregnancies, both naturally and through assisted reproductive techniques. The approach should be realistic but not defeatist, considering all available options tailored to each particular case.
Future Perspectives and Considerations
Research on AMH continues to evolve, promising broader and more precise applications in the future. Recent advances point towards the use of AMH not only as a marker of ovarian reserve but also as a predictor of menopause age and a tool for evaluating various gynecological conditions.
Longitudinal studies suggest that monitoring changes in AMH levels over time could provide more valuable information than isolated measurements. A study published in Fertility and Sterility found that "the rate of AMH decline may be a better predictor of ovarian response than a single value" (Martínez et al., 2021).
In the clinical realm, algorithms are being developed that integrate multiple biomarkers, including AMH, to create more accurate predictive models regarding fertility and treatment response. These models consider factors such as age, BMI, lifestyle habits, and other hormonal markers to offer personalized assessments.
New Clinical Applications
The utility of AMH is expanding beyond fertility. Recent research explores its role in:
- Prediction of metabolic syndrome in postmenopausal women
- Assessment of cardiovascular risk
- Monitoring ovarian function during and after cancer treatments
- Diagnosis and follow-up of granulosa cell tumors
In the field of oncofertility, AMH is emerging as a crucial tool for assessing the impact of cancer treatments on ovarian function. This allows for the development of personalized fertility preservation strategies for young patients diagnosed with cancer.
It is important to remember that, despite these advances, AMH remains only one piece of the complex puzzle of fertility. Reproductive decisions should be based on a comprehensive evaluation, considering medical, personal, emotional, and practical factors.
As science progresses, it is likely that additional biomarkers and more sophisticated technologies will emerge to assess reproductive potential. Nevertheless, AMH will continue to play a fundamental role in reproductive medicine due to its reliability and demonstrated clinical utility.
Frequently Asked Questions
- Can I get pregnant with low AMH levels?
- Yes, it is possible to conceive with low AMH levels. Although these levels indicate reduced ovarian reserve, they do not reflect the quality of the remaining eggs. Many women with low AMH achieve pregnancies, especially if they are relatively young. Options include natural conception, personalized fertility treatments, or, in some cases, consideration of donor eggs.
- How often should I have the AMH test?
- For most women, it is not necessary to repeat the AMH test frequently. However, if you are planning fertility treatments or considering egg preservation, your specialist may recommend an initial evaluation and follow-up based on your specific situation. Generally, measuring every 1-2 years is sufficient if there is concern about ovarian reserve.
- Can AMH levels improve with treatments or lifestyle changes?
- Currently, there is no solid scientific evidence supporting that AMH levels can be significantly increased through treatments or lifestyle modifications. AMH primarily reflects genetically determined ovarian reserve, which naturally decreases with age. However, maintaining a healthy lifestyle benefits overall reproductive health and may optimize egg quality.
- Can AMH predict when menopause will occur?
- AMH levels can provide an approximate estimate of the age of onset of menopause, although with limitations. Very low values in young women may suggest an earlier menopause, while higher levels may indicate an ovarian reserve that will last longer. However, individual predictions still lack absolute precision and should be interpreted with caution.
Summary
The anti-Müllerian hormone (AMH) represents a valuable tool for assessing ovarian reserve in the context of female fertility. Produced by developing ovarian follicles, its serum levels reflect the approximate number of remaining eggs, providing crucial information for reproductive planning and the design of fertility treatments.
It is essential to understand both the value and limitations of AMH. While it offers valuable information about the quantity of eggs, it does not indicate their quality nor predict with certainty the chances of conception. The interpretation of results should be made in the context of age, other reproductive parameters, and each woman's personal goals.
For women planning their reproductive future, AMH represents an important piece of the puzzle, but not the only one. Decisions about when to try to conceive, whether to preserve eggs, or consider fertility treatments should be based on a comprehensive evaluation that considers multiple factors. With the appropriate guidance from reproductive medicine specialists, this information can significantly contribute to informed decisions about reproductive health.
Are you thinking about starting fertility treatment? At Avida Fertility, we provide personalized care and all the attention you deserve. Schedule your consultation today and take the first step towards the dream of starting your family.
References
- González, M. (2023). Advances in the clinical interpretation of anti-Müllerian hormone. Spanish Journal of Fertility, 41(2), 78-85.
- Chen, Y., Liu, L., Feng, Y., & Zhang, Y. (2022). AMH levels predict IVF outcomes and live birth rates in women undergoing assisted reproductive technology. Journal of Clinical Endocrinology & Metabolism, 107(5), e2021-00325.
- Martínez, F., Clua, E., & Rodríguez, I. (2021). Longitudinal changes in serum anti-Müllerian hormone levels and their relationship with ovarian response. Fertility and Sterility, 116(4), 1156-1165.
