The Truth about AMH and Fertility

SPOILER: It's not a crystal ball for your fertility

Anti-mullerian hormone (AMH) is a serum (or blood) marker for ovarian reserve. It’s a hormone that is secreted by the developing follicles and gives us insight into how many follicles are recruited each cycle (this can also be measured directly via ultrasound - called antral follicle count). Many of us get caught up in our "egg count" as the ultimate marker of fertility but that's not the whole story...

What is a "Normal" AMH 

AMH ranges are based on age. AMH typically peaks around 20-25 y/o and naturally declines with age. The average yearly decrease in AMH value was 0.2ng/mL/year through age 35 and then 0.1 ng/mL/year after age 35. It’s important to note that these are averages and we don’t know how quickly it will decline for each individual.

Since AMH naturally decreases as we age, and younger women (<35 years old) with an AMH <1.0ng/mL should have further investigations for low ovarian reserve.

Check out the table for normal ranges based on age, NOTE: These ranges are in pmol/L, the other commonly used metric is ng/mL (you can do the conversion here: https://unitslab.com/node/155)

What if I have Low AMH for My Age?

Serum AMH levels have poor predictive value for natural pregnancy. This means a low AMH doesn’t mean you can’t conceive naturally. In women <40, AMH does not predict the chances of natural conception per cycle or live birth rates once pregnancy is achieved. 

If we look at the graphical representations below, they show the stratification of high, normal and low ovarian reserve (measured with AMH and antral follicle count) and compare it to pregnancy rates.

Source: Nelson, Fertil Steril, 2013

Source: Zarek. JCEM 2015

Over 3, 6, 9 and 12 months women with low AMH are as likely to get pregnant as those with normal or high levels. This is true for both older (>35) and younger (<35) women who are trying to conceive. Again, AMH is NOT a predictor of your ability to achieve a natural conception.

What about AMH and IVF?

This is where AMH is useful, it is an important predictor of IVF success and response to ovarian stimulation. A low AMH typically results in a poorer response in women to controlled ovarian stimulation, resulting in fewer eggs and pregnancies than in women of a similar age. The inverse is true, a high AMH (most commonly seen in PCOS), puts women at higher risk for ovarian hyperstimulation syndrome (OHSS).

In conclusion, navigating the challenges of PCOS requires understanding its complexities, managing symptoms effectively through lifestyle changes and medications, and seeking support from healthcare providers and peers. By taking control of your health and advocating for yourself, you can thrive despite having PCOS.