If your FSH levels are high, does that mean you are infertile? The simple answer is no. But it doesn’t mean that FSH levels do not have an impact on your fertility. The fact is, FSH is actually essential to your capability to become pregnant and you should know more about this hormone if you plan to get tested.

FSH actually stands for follicle stimulating hormone. It is produced by the pituitary gland along with other hormones to regulate specific functions of the body. As you can guess from its name, this hormone regulates the growth of follicles. In reproduction, follicles are essential in both men and women because they are needed for sperms and eggs to grow. In a woman, the follicles form the sacs that store the eggs in the ovaries. If the body creates more eggs, it will need more storage space and hence more follicles. The pituitary gland gets the message from the body and produces more FSH. The body in turn responds to the presence of FSH and produces more follicles. Once the body produces enough follicles, it sends a message to the pituitary gland to stop producing FSH. But if your body can’t create the follicles, for whatever reason, the pituitary gland won’t get the stop message and will continue to flood your body with FSH. This is why doctors use it as an indicator for fertility problems. A high level of FSH will usually indicate a problem with follicle production and will point to a low egg count, referred to as the ovarian reserve. Hence, if your doctor suspects that you are having difficulty conceiving because of low ovarian reserves, expect an FSH test.

FSH levels are tested through a sample of your blood taken at the third day of your menstrual cycle (some doctors take samples on the second or fourth day and this is also acceptable). This period should yield generally normal or stable levels of FSH if follicle production is functioning properly. A normal value would be something like 15 mIU/ml (this is the unit for FSH, more formally known as milli-international units per milliliter) or lower. If the number is higher than 25, this could be a sign that your ovarian reserves are low. Again, this does not mean you are infertile. There were studies that even people with FSH numbers in the hundreds ending up getting pregnant with minimal support. It does lower the chances of pregnancy though.

Don’t take these numbers as absolute baseline figures though. Because the different laboratories that may conduct the test will have different processes and equipment, the results may have different meanings and it is best to interpret them with the help of a health professional. Try to keep in mind that the FSH numbers are only one of the numbers that doctors will look at so don’t base any decision on their numbers alone.

In fact, having low FSH levels isn’t always the best news. Sometimes the problem is not in the capability to produce follicles but in the pituitary glands capability to produce the hormone. This will result in really low FSH levels and will equally hamper your ability to get pregnant. This situation, however, can be treated with FSH. By injecting FSH into your body, the follicle production process is started, bypassing a possible defect or problem in the pituitary gland. Cases of anovulation and polycystic ovarian syndrome are treated this way.

So there it is. Some facts that will help you face one of the tests that you may have to go through in your path to pregnancy. However, FSH is just one of the tests and you will probably have to go through a gauntlet of tests before you can determine the details of your situation. But with more knowledge, you can make the journey a little smoother and a little less stressful.