PCOS and Anti-Müllerian Hormone

Anti-Müllerian hormone (AMH) is secreted by an ovarian follicle as it gets ready to release an egg during the menstrual cycle. The hormone also goes by the name Müllerian-inhibiting substance.

AMH levels are directly related to how many small follicles are found on the ovary each month. These are called antral follicles.

This article will cover how AMH can be used to help diagnose a person with a condition called polycystic ovarian syndrome (PCOS).

Ovarian Follicles and AMH

Antral follicles are also called resting follicles. Throughout the menstrual cycle, follicles pop up on the ovaries and go through changes. Antral follicles are in the later stages of development.

Eventually, the follicles get to the end of their development and become mature. A mature follicle has the potential to release an egg. This is called ovulation.

The more antral follicles a person has, the higher their AMH levels will be. Doctors can use a person’s AMH levels to estimate how many follicles a person has. This is known as ovarian reserve.

Knowing this number can be helpful in some fertility situations. For example, if a person is going to have in vitro fertilization (IVF), knowing how many follicles they have can give them a sense of their chances of success.

AMH and PCOS

People who have polycystic ovary syndrome (PCOS) have a lot of antral follicles. This means they also have high levels of AMH. High AMH levels can suggest PCOS in people who may not have symptoms of the condition.

Having too much AMH can stop ovulation from happening. In a normal ovary, AMH keeps the follicles from developing too early. If this happened, they would release an egg that isn’t ready yet.

However, when AMH levels are too high, they “put the brakes” on and stop an egg that is ready from being released.

What AMH Levels Mean

AMH levels can be measured with a blood test. A person can have their blood taken on any day of their menstrual cycle. The sample is sent to the laboratory for analysis to determine if a person’s AMH level is low, normal, or high.

A high level by itself is not enough to diagnose PCOS because AMH levels vary over a lifetime, and usually get lower as a person ages. Doctors compare a person’s age to their AMH results to make a diagnosis.

How AMH Helps Diagnose PCOS

AMH can be very helpful in suggesting a diagnosis of PCOS in people over the age of 35. To confirm a PCOS diagnosis, a person also needs to meet at least two of the following criteria:

1. Irregular or missed periods suggesting delayed or no ovulation (oligomenorrhea)
2. An ultrasound that shows multiple cysts on the ovaries (polycystic)
3. Lab results showing increased levels of hormones called androgens or physical signs of high levels (e.g., abnormal hair growth, acne)

Meeting the criteria for a diagnosis can be harder for people over the age of 35. It’s rare to see polycystic ovaries on ultrasound in people in this age group. If a person doesn’t have the typical signs and symptoms of PCOS, the diagnosis can be missed.

However, if a doctor sees that a person has a high level of AMH, it could point them toward a possible PCOS diagnosis.

The AMH test can also be useful for people who know they have PCOS. People with PCOS who have higher levels of AMH tend to have worse symptoms.

Summary

Anti-Müllerian hormone (AMH) is put out by antral follicles on the ovary when it’s getting ready to release an egg. The more antral follicles a person has, the higher their AMH level will be.

AMH levels can help diagnose polycystic ovarian syndrome (PCOS). People with the condition often have AMH levels that are high.

Sometimes, it’s hard to diagnose PCOS because a person may not have specific symptoms. They might also think that common PCOS symptoms like acne are being caused by something else.

A person who has PCOS may have worse symptoms if their AMH level is high.

A Word From Verywell

If you have symptoms of PCOS, talk to your doctor. If you’re over the age of 35, it might be harder to get a diagnosis of PCOS because you might not fit all the criteria. Having your AMH level checked can help your doctor figure out if you might have PCOS.