Out of all the hormones we know, anti-Mullerian hormone (AMH) might not be the most well known or talked about. But with respect to reproductive health, it’s definitely an important hormone & worth understanding, especially if you’re hoping to get pregnant in the future.
Women are typically born with a certain number of eggs, about a million. Throughout their life, women ovulate and these eggs keep getting used up. Anti-Mullerian Hormone is a glycoprotein hormone produced by your ovarian follicles & is a good indicator of your egg reserve. AMH levels are fairly constant throughout the menstrual cycle & can be tested anytime during the cycle.
Men also produce AMH but it is of no consequence to male fertility. For females, a value of above 1.0 ng/ml is considered normal. Low AMH levels are indicative of diminished ovarian reserve (DOR) or, low egg count. In other words, if a woman has DOR, the number of eggs she has are beginning to decrease. Women with higher AMH, will tend to have a better response to ovarian stimulation for IVF.
Low AMH may indicate DOR but it isn’t the full picture. It does not reveal if your eggs are of good quality or not. There are other hormonal tests which also may be done in addition to AMH along with a transvaginal ultrasound to count the number of antral follicles. A combination of theses tests is always a better way of assessing the fertility potential!
However, in case you’re planning to go in for IVF, AMH can well be used to gauge the number of eggs you may produce along with the dosage of medication you’ll need to stimulate egg production.
What are the causes low AMH?
AMH levels depend on the number of developing follicles in a woman’s ovaries. The most crucial factor is age, because ovarian reserve does decrease as women age. Ovarian reserve begins to diminish in and around the mid to late 30s, and AMH levels will most likely be even lower in women who are in their 40s. However, age is not the only determining factor for low AMH. Some women have high AMH levels well into their 40s, while others will face falling AMH levels even in their 20s or 30s. This can happen because of environmental factors, for example; if someone has been receiving cancer treatment, or has an inherited genetic disease.
It’s important you find out the average age by which women in your family face menopause as this is quite often a good indicator for the rate of your own fertility decline. Ageing will naturally reduce egg reserves. However, there are other factors that can cause low AMH such as, endometriosis, any ovarian surgery in the past, chemotherapy, radiation therapy, smoking, pelvic infections, autoimmune diseases and genetic abnormalities such as fragile X syndrome.
We’ve had patients with diminished ovarian reserve get pregnant with their own eggs after receiving treatment. However, we always maintain that in treating infertility, timely & early diagnosis is crucial, as it will always give you a much better chance of conceiving. The treatment for DOR may start with supplements containing mild androgens like DHEA, which can increase fertility. If low AMH is diagnosed soon enough, it’s best to have your eggs frozen as early as possible when they’re relatively healthy, even if their number is reduced. You could then choose to go in for IVF with the frozen eggs immediately, or later on use as per your convenience.
The bottom line is that low AMH does not mean you can’t conceive; all you need is a guiding hand to take it further.