The 411 on AMH
LAST UPDATED: Feb 11, 2019
4 MIN READ
HERE'S WHAT WE'LL COVER
Heads up before we begin: We’re about to get technical. That’s because the more you understand about your hormones in general — and specifically your anti-Mullerian hormone (AMH) — the better you can understand your fertility. This is a brief overview of AMH, but if you want to dive even deeper into the hormone, check out the Modern guide to AMH.
AMH is one of the best indicators of the number of eggs in your ovaries, or your ovarian reserve. The hormone is produced by the preantral and antral follicles in the ovaries. Preantral and antral follicles are the developing follicles in your ovaries — in other words, they correlate with the number of eggs available for ovulation (though it’s important to keep in mind that this number only gives you an idea of quantity, not quality):
The lower the AMH level, the fewer remaining ovarian follicles and the lower the ovarian reserve.
The higher the AMH level, the higher the number of remaining ovarian follicles and the higher the ovarian reserve.
While your AMH level isn’t a crystal ball into your fertility future — meaning it is not a predictor of your ability to conceive today or at a certain time in the future — it does give you more info about your reproductive health: an understanding of your ovarian reserve, egg freezing or IVF outcomes, menopause timing, and conditions like polycystic ovarian syndrome (PCOS) and premature ovarian insufficiency (POI). Understanding your AMH level can help inform your timeline for getting pregnant and can fuel conversations with your doctor.
AMH levels over time
As you get older, AMH and ovarian reserve decline. We’re born with 1-2 million eggs, but each month, 800-1,000 eggs undergo natural cell death. It only takes one to make it to the finish line (ovulation) — if the egg gets fertilized, that may result in a pregnancy. If not, you get your period. This happens every month, although if you’re on hormonal birth control (like the pill), you may not be ovulating or getting a period.
AMH generally peaks at age 25, and then AMH (and egg count) begin to gradually decline. Around age 35 (it’s different for every individual), ovarian reserve decline becomes more rapid. By menopause, egg count and AMH drop to undetectable levels.
What low and high AMH (for your age) may indicate
People with lower AMH for their age are likely to have a lower number of eggs than expected and a shorter reproductive window than those with normal AMH for their age. If your level is low and you’re on the younger side, this could be a sign of a diminished ovarian reserve. Tracking your level over time will help you get a handle on the rate at which your ovarian reserve is declining and, while it is very rare, whether premature depleted ovarian reserve could be a possibility for you.
Very low AMH, absent periods, and perimenopausal symptoms could be signs of primary ovarian insufficiency (POI). Dr. Shaun Samples, an OB-GYN in Nashville, defines POI as “the loss of eggs in the ovaries or abnormal function of the ovaries, so that periods and the entire menstrual cycle cease for large stretches of time or permanently before the age of 40.” (Note that only 1 in 100 people with ovaries will be diagnosed with POI — 25% of them may spontaneously ovulate, and 5% to 10% will conceive and deliver after being diagnosed with POI.)
A high AMH level means that you have a higher number of eggs than is expected for your age. It’s also often linked (shown here, here, here, and here) to polycystic ovary syndrome (PCOS): a common hormonal disorder that impacts 1 in 10 people with ovaries. One of the symptoms of PCOS is a large number of follicles that have stopped developing in the ovaries, leading to irregular cycles and difficulty timing intercourse around ovulation. Even though most people with PCOS have a higher number of follicles, they don’t all reach full development because of extra androgens (“male” sex hormones like testosterone) in the body.
In addition to issues with fertility, PCOS can lead to pregnancy complications and increased risk of diabetes, cardiovascular disease, endometrial cancer, anxiety, and depression. Early diagnosis can help better treat PCOS and any related conditions. (Hormonal birth control is a common medication option for those with PCOS.)
AMH + fertility treatments
Your AMH levels can help you prepare for fertility treatments, like in-vitro fertilization (IVF) and egg freezing. Ovarian stimulation is the stage of IVF in which you're given drugs to –– you guessed it –– stimulate your ovaries to mature multiple eggs at once, instead of the normal one egg per cycle. The number of eggs that can be retrieved from your ovaries depends on your ovarian reserve –– which your AMH levels clue you in to. If you have low levels of AMH, it's harder to predict how you'll respond to ovarian stimulation. Low AMH can also mean that you may have to do more than one cycle of IVF to get enough eggs to fertilize. Understanding your ovarian reserve can help you plan financially, mentally, and physically for the possibility of multiple cycles.
In terms of egg freezing, whether your AMH level is high or low, it can give you more info to help you make the decision to freeze your eggs or not (based on predicted chances of success during egg retrieval procedures). Birth doula and writer English Taylor used her AMH level to think about proactively freezing her eggs. As she explains, “By freezing my eggs now (with higher AMH), I could be saving my future self some major dough.” Why’s that? Because AMH declines as we age, more harvesting rounds may be needed later in life to get viable eggs. (Keep in mind, though, that freezing your eggs is not an insurance policy for future fertility.)
That said, an important thing to remember is that AMH levels don’t reflect egg quality. Having more eggs at the egg retrieval provides an opportunity for a greater number of eggs to be fertilized and to develop into embryos, but more eggs does not always mean more embryos. That’s because not all of the eggs we produce are viable or healthy. Still, understanding the current status of your ovarian reserve can help you make an informed decision about your options.
The bottom line
Knowing and understanding your AMH levels isn’t going to give you all the answers about your fertility present and future. It will, however, give you information that can help you start conversations with your doctors about next steps and prepare for the life you want.
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.