FSH test is a blood test that measures the level of follicle stimulating hormone. It’s an important part of female fertility workup, because this hormone is central to a woman’s ovarian function and fertility. “Follicle” in the name of this hormone is a sack that forms around an immature egg and provides nutritional support to the egg in a woman’s ovaries. At the time of ovulation, one follicle typically releases an egg that has fully matured to travel through the fallopian tube to eventually meet with a sperm. The formation of follicles is controlled by follicle stimulating hormone, which is what is measured by an FSH test.
How to Test Egg Quality: Fertility Testing with FSH and LH Blood Tests
The FSH test is often considered a blood test for egg quality. In truth, the FSH test doesn’t directly measure egg quality; rather, it measures ovarian reserve, which determines the competency of eggs in the ovaries. Furthermore, a number of other tests, including the AMH test, are needed for a complete picture of a woman’s fertility. The full fertility workup is what helps us create a treatment plan that’s highly specific to each patient’s needs.
The level of follicle stimulating hormone in the bloodstream changes throughout a woman’s menstrual cycle. It rises slightly in the first few days of the cycle, remains stable for about ten days, then peaks during ovulation, when the follicle releases a mature egg. After ovulation, FSH falls and remains low until after the next cycle begins. Luteinizing hormone (LH), another reproductive hormone produced by the pituitary gland, follows a similar pattern. Often, the fertility hormone test is performed as a combined FSH-LH test.
In order to have a standard reference point, physicians have established a standard point in the menstrual cycle for conducting the test. FSH test is typically performed as a day 2 or day 3 blood test, meaning that you will need to have it on the second or third day of your period. About 8 mL of blood is necessary. (Usually at CHR, another 8 mL is drawn at the same time for other hormone tests like AMH, LH, estradiol, etc.) Once the blood is drawn, it’s spinned and analyzed for the amount of follicle stimulating hormone. CHR runs FSH analysis in-house if the patient’s insurance is in-network; if not, the blood is sent out to an in-network lab for analysis.
FSH Test Results Interpretation
After the lab returns your results, one of our physicians will conduct a detailed review of the values, along with other tests that are part of the fertility workup. At CHR, FSH test results interpretation is always a part of understanding the bigger picture: We look at the result alongside everything else that helps us assess why you may be having trouble becoming pregnant. This comprehensive approach is a part of why we can usually pinpoint the exact cause of infertility where other centers may give you an unexplained infertility diagnosis.
Another important part of CHR’s approach to interpreting FSH test results, as well as AMH test results, is the use of age-specific baseline values (which we’ve listed in the table below). The level of follicle stimulating hormone, like other hormone levels, changes naturally throughout a woman’s life, which means that what should be considered a “normal” FSH level changes depending on the patient’s age. Using a universal “normal” value, a standard practice for decades in the infertility treatment setting, leads to some younger patients with abnormal ovarian function for their age going undiagnosed.
FSH Test Normal Range: Is it Better to Have High or Low FSH?
It may sound paradoxical, but lower follicle stimulating hormone test results are associated with an easier time conceiving. This is because of the body’s feedback loops. As we get older, quality and quantity of eggs decline. In response, the pituitary gland works harder to produce more follicle stimulating hormone to try to encourage more eggs to develop. Therefore, a low number on your FSH test means that your ovaries are functioning well, pushing a good number of eggs through the maturation process, while a high level signals diminished ovarian reserve (DOR) with few eggs getting ready for ovulation every month.
FSH Test Results Normal Range by Age
Below is a chart we’ve created to summarize the normal FSH test ranges (as well as AMH hormone levels) by age. Using age-specific normal values for AMH and FSH enables our physicians to identify younger women with early stages of ovarian problems, which in turn lets us tailor the treatment, as well as provide a more nuanced IVF prognosis to older women based on their ovarian function. Learn more about IVF after 40 here.
Age Specific Baselines for FSH Test Result Interpretation
|FSH Test Normal Range|
|Age||(Day 3 Blood Test)||AMH Test Normal Range|
|< 33 Years||< 7.0 mlU/mL||= 2.1 ng/mL|
|33-37 Years||< 7.9 mIU/mL||= 1.7 ng/mL|
|38-40 Years||< 8.4 mIU/mL||= 1.1 ng/mL|
|= 41+ Years||< 8.5 mIU/mL||= 0.5 ng/mL|
FSH Test Results and What to Expect
Some tests in the initial fertility workup may take a few weeks to return results. After all the test results are in, you will have a follow-up consultation with one of our physicians to discuss them, including your FSH result viewed against the FSH test normal range for your age. Then, your physician will design a fertility treatment plan that addresses the specific fertility issues identified during the workup and discuss what you can expect from different treatment options.
IVF with High FSH Levels
Blood tests for FSH and AMH give our physicians a sense of each patient’s ability to produce a good number of high-quality eggs, which is an important indicator of the potential success of an in vitro fertilization (IVF) cycle. Learn more about interpreting your follicle stimulating hormone levels.
Patients with high FSH test results often feel helpless, but these test results don’t just tell us about the patient’s condition; the results also enable the clinical team at CHR to tailor the ovarian preparation and stimulation protocols precisely to each patient’s ovarian reserve status so that they’ll have the best chance at pregnancy with IVF.
What Do High FSH Levels Mean for IVF?
High FSH levels, as well as abnormally low AMH and/or AFCs (antral follicle counts), denote a relatively poor fertility prognosis and low probability of success with IVF, but there are ways to address this issue, including ovarian preparation with androgen supplementation (typically with DHEA), careful monitoring of androgen and SHBG levels, highly individualized egg retrieval (HIER) and more.
Norbert Gleicher, MD, leads CHR’s clinical and research efforts as Medical Director and Chief Scientist. A world-renowned specialist in reproductive endocrinology, Dr. Gleicher has published hundreds of peer-reviewed papers and lectured globally while keeping an active clinical career focused on ovarian aging, immunological issues and other difficult cases of infertility.
Read more about High FSH
FSH (follicle stimulating hormone) is a hormone released by the pituitary gland...
A few years ago, CHR's research established age-specific levels of FSH and AMH...
Last Updated: April 23, 2020