To get a sense of how many eggs you produce each month and start to get a picture of your overall fertility potential, your clinician may order an AMH (anti-müllerian hormone) test. But what is AMH and what can it tell you about your fertility?

Six Second Snapshot:

• By measuring the amount of AMH in your blood, your clinician can get a good idea of how many follicles remain in your ovaries.
• A normal AMH level tends to fall between 1-3.5 ng/ML.
• Because AMH levels tend to decrease with age, as the ovaries produce fewer follicles each month, it’s best to consider how your AMH falls within your age range.
• You can have your AMH tested on any day of your menstrual cycle.

What is anti-müllerian hormone (AMH) and why does it matter?

Let’s start by talking about follicles – tiny, fluid-filled sacs in your ovaries, each containing an immature egg. It may surprise you to know that if you have ovaries, you are born with all the follicles you will ever have! These follicles stay dormant until they are recruited to grow by a carefully orchestrated series of hormones. Once recruited, the follicles grow and develop for about 300 days, during which they begin to secrete a protein called anti-müllerian hormone (AMH). Over time, most of these follicles die off in a process called apoptosis, so that only one egg on average reaches maturity and is ovulated.

Since the number of follicles growing in your ovaries corresponds to the amount of AMH in your blood, measuring your AMH can give your doctor a sense of how many follicles remain in your ovaries (1), also known as your ovarian reserve.

If you are planning to undergo in vitro fertilization (IVF), your AMH blood test will help your clinician predict how many eggs you might retrieve in an IVF cycle.

What is a normal AMH level, and what does it mean if I have a high or low AMH?

A normal AMH level tends to fall between 1 - 3.5 ng/mL.

Low AMH levels may indicate low ovarian reserve (also known as diminished ovarian reserve). This doesn’t necessarily mean that it’s impossible to get pregnant; after all, you need just one egg to get pregnant! However, it is an indicator that you have fewer follicles in your ovaries. This is particularly relevant for IVF, during which doctors will try to retrieve many eggs per cycle in order to give you the best chance of success.

Alternatively, a high AMH may indicate polycystic ovary syndrome (PCOS), a hormone imbalance that may make it difficult to conceive.

Because AMH tends to decrease with age, as the ovaries produce fewer follicles each month, it’s best to consider how your AMH falls within your age range. To understand where you fall, here is a graph of a range of AMH levels by age:

How and when do they test for AMH?

While some baseline fertility tests need to be performed on a certain day of your menstrual cycle, AMH doesn’t fluctuate much since it’s largely produced by immature follicles. As a result, you can have your AMH tested on any day of your menstrual cycle. Also, though your AMH may fluctuate slightly from test to test, your ovarian reserve does not (waiting for a better AMH result will not improve your outcome from IVF.)

For an AMH test, a phlebotomist will conduct a simple blood test: they will draw some blood from your arm and send it to the lab. You will typically get your results from the test within the week.

AMH test kits are available over-the-counter, as well, and use a finger prick blood sample to conduct the test. However, for a complete picture of your fertility, it is best to see a fertility specialist who can help you interpret the test results and order additional tests to get a more holistic picture of your ovarian reserve and fertility potential. A fertility specialist can also identify specific reasons why you may be experiencing infertility, such as endometriosis or tubal factor infertility.

How does AMH relate to FSH and AFC?

Follicle stimulating hormone (FSH) is secreted by the pituitary gland to stimulate follicle development and control the menstrual cycle. As a result, FSH is another valuable window your fertility specialist may use to understand your fertility potential.

Since FSH helps to regulate the menstrual cycle, the FSH test needs to be conducted on a specific day, typically 2-4 days after your menstrual cycle begins. High FSH levels and low AMH at this point of the cycle may indicate poor ovarian function, menopause, or perimenopause. Conversely, low FSH levels may indicate pituitary gland dysfunction or PCOS.

If you are getting baseline fertility tests conducted, your fertility specialist will likely also order a baseline ultrasound about 2-5 days after your menstrual cycle begins to check on your antral follicle count (AFC). Your AFC will be the number of follicles above 8 mm that you have that month. Together with your FSH and AMH, your AFC will contribute to your fertility specialist’s picture of your potential success with infertility treatment.

What DOESN’T an AMH test tell you?

While an AMH test can help your clinician understand the quantity of follicles you may develop each menstrual cycle, it doesn’t give them information about your egg quality. For example, ten eggs retrieved from a patient under 30 for IVF are more likely to be chromosomally normal than ten eggs retrieved from a patient over 40, even if their AMH levels are the same.

Testing your AMH levels before undergoing egg freezing or IVF helps your doctor understand your potential success with infertility treatment, since having a greater ovarian reserve gives you a greater chance of success. Your AMH will also help to determine your medication protocol for ovarian stimulation during IVF.