From the Guidelines
No, Anti-Mullerian Hormone (AMH) levels are typically elevated, not low, in women with Polycystic Ovary Syndrome (PCOS). In fact, high AMH levels are often used as a diagnostic marker for PCOS. Women with PCOS usually have AMH levels 2-3 times higher than women without the condition. This elevation occurs because PCOS is characterized by an increased number of small antral follicles in the ovaries, and these follicles produce AMH. The more follicles present, the higher the AMH level. This is consistent with the polycystic appearance of the ovaries on ultrasound, which shows multiple small follicles arranged in a "string of pearls" pattern. While AMH levels naturally decline with age as ovarian reserve diminishes, women with PCOS tend to maintain higher AMH levels throughout their reproductive years compared to women without PCOS. If a woman suspected of having PCOS has low AMH levels, other causes for her symptoms should be investigated, as this would be inconsistent with typical PCOS presentation. According to a review informing international guidelines, AMH levels could potentially replace ultrasound in PCOS diagnosis once issues with standardization and sample handling are addressed 1. Some studies have also found that women with functional hypothalamic amenorrhea (FHA) and polycystic ovarian morphology (PCOM) have higher AMH levels compared to those without PCOM, suggesting that some FHA patients with PCOM may have originally had PCOS before developing FHA 1.
Some key points to consider:
- AMH levels are typically elevated in women with PCOS
- High AMH levels are often used as a diagnostic marker for PCOS
- Women with PCOS tend to maintain higher AMH levels throughout their reproductive years compared to women without PCOS
- Low AMH levels in a woman suspected of having PCOS should prompt investigation into other causes of her symptoms
- Standardization and sample handling issues need to be addressed before AMH levels can be used as a reliable diagnostic tool for PCOS 1
- FHA patients with PCOM may have originally had PCOS before developing FHA, and may have higher AMH levels compared to those without PCOM 1.
From the Research
Anti-Mullerian Hormone (AMH) Levels in Polycystic Ovary Syndrome (PCOS)
- AMH levels can be variable in cases of PCOS, and while they are often elevated, there are instances where they can be low 2.
- A study found that serum AMH levels peaked before 25 years of age and decreased with age, with 72.1% of patients with PCOS having an AMH result in the top quartile for their age 2.
- However, another study noted that both groups of non-obese PCOS women undergoing mild stimulation with letrozole plus hMG or conventional IVF stimulation protocols showed lower than expected AFC and AMH values as a consequence of metformin pre-treatment 3.
- The variability in AMH levels in PCOS patients suggests that AMH can be low in some cases, particularly in those undergoing certain treatments such as metformin pre-treatment 3.
Factors Influencing AMH Levels in PCOS
- Age is a significant factor influencing AMH levels, with levels decreasing as age increases 2.
- Metformin pre-treatment can also affect AMH levels, with studies showing lower than expected AMH values in non-obese PCOS women undergoing metformin pre-treatment 3.
- The use of certain medications, such as letrozole, can also impact AMH levels, although the exact relationship between letrozole and AMH is not fully understood 3, 4.
Clinical Implications of Low AMH Levels in PCOS
- Low AMH levels can indicate a reduced ovarian reserve, which can impact fertility treatment outcomes 2.
- However, the relationship between AMH levels and fertility treatment outcomes in PCOS patients is complex, and other factors such as age, BMI, and medication use can also influence treatment success 5, 6.
- Further research is needed to fully understand the clinical implications of low AMH levels in PCOS patients and to develop effective treatment strategies for this population 5, 6.