FSH is a hormone that plays a crucial role in both male and female sexual development and function, and its levels may be measured via a blood or urine test. While there is no significant role of FSH during pregnancy as it remains low throughout the pregnancy, your doctor may suggest this test during prenatal visits to rule out specific disorders. Read this post to know more about FSH, its importance during pregnancy, and how the test is done.
What Is The Meaning Of FSH?
FSH is the shorter term used to refer to the follicle stimulating hormone. It is one of the many hormones that are secreted by the pituitary gland. FSH stimulates your ovaries and helps to produce mature eggs. It also helps to regularize your menstrual cycle. In men, it helps to produce sperm. The FSH, along with the luteinizing hormone, helps to take care of many important functions in your body. 
What Should Be FSH Levels During Pregnancy?
Ideal FSH in pregnancy are extremely crucial while you are pregnant. It helps to form the placenta, especially during the initial months of your pregnancy. When you are pregnant, your FSH levels should ideally be below 2 mlU/ml. Remember that while you are pregnant, your body will go through a lot of changes . As your pregnancy progresses, your FSH levels should definitely be between 3 to 10 mlU/ml.
What Conditions Can Lower The FSH Levels?
There are various conditions that may lower your FSH levels: 
- A condition known as anorexia nervosa can lower your FSH levels extensively.
- Any disorder in the hypothalamus can cause a dip in your FSH levels.
- Any disorder in the pituitary gland can also make your FSH levels go extremely low.
What Do Low FSH Levels Indicate?
Your FSH levels during pregnancy will generally be too low to be measured properly. This might look like the levels are very low. A low count of FSH could indicate the following conditions: 
- A condition known as hypopituitarism, where your pituitary gland does not produce the hormones it is supposed to produce. In some cases, it may produce them in very low quantities.
- Very poor FSH levels can also indicate a condition known as Turner syndrome. It is a chromosome related condition and affects the development and growth in females.
How Do You Prepare For The FSH Test?
There are a few steps that have to be followed before going for the FSH test. While you are pregnant, there may be certain variations keeping your condition and health in mind. Speak to your doctor first to know how you should prepare before going for the test. Here are the steps that are generally followed in preparation: 
You will not have to stop any fluid or food intake. You can eat your normal diet.
Your doctor may ask you to stop taking any medications 48 hours prior to the test. Speak to your doctor about your pregnancy and mention the medications you are currently taking. Your doctor may ask you to stop all or a few of them. In some cases, your doctor may allow you to continue with medication even when you are about to go for the test.
Are There Any Special Precautions To Be Taken After The Test?
There are no special precautions that you need to take. However, make sure you inform the health care provider about your pregnancy. In case you feel dizzy or uncomfortable during or after the test, ask for assistance and sit down where you are comfortable.
Can The Test Of FSH During Pregnancy Cause Any Side Effects?
The FSH test is considered absolutely safe and does not have any known side effects. If you feel uncomfortable or dizzy at any time during or after the test, tell your healthcare provider about it.
Frequently Asked Questions
1. What happens to LH and FSH levels during pregnancy?
Serum follicle-stimulating hormone (FSH) levels can remain low and return to normal levels in the follicular phase around 20 days after delivery. During the early weeks of pregnancy, the FSH levels can be around 0.1international units (IU). Luteinizing hormone (LH) surge is not seen in pregnancy, and it may remain at low levels in pregnancy (1).
2. Does high FSH cause miscarriage?
Elevated FSH levels are associated with unexplained recurrent pregnancy loss (RPL) or miscarriage in some women. This can be due to diminished ovarian reserve (2).
3. Is it possible to conceive with high FSH?
Studies have shown that the conception rate was low or nonexistent, with an FSH value greater than 15. Some pregnancies occur in women with FSH levels between 10 and 15 IU. Many IVF clinics accept FSH values less than 10 for their selected candidates (3).
4. What is a good FSH level for fertility?
FSH values can be between 4.7 to 21.2 in women still menstruating. The indicated values may vary based on the test and other factors (4).
Follicle stimulating hormone or FSH during pregnancy usually remains low. In women, the hormone stimulates the release of eggs from the ovaries. Disorders of the pituitary gland or hypothalamus may reduce FSH secretion. Additionally, Turner syndrome may cause low FSH levels. An FSH test may be suggested during pregnancy to screen for certain disorders. Some medications may alter the results of an FSH test, so you may inform your doctor beforehand about the medicines you are using before taking the test.