When we talk about the FSH blood test, FSH stands for follicle stimulating hormone. Follicles are sacs that form around immature eggs and provide nutritional support to these eggs 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. The formation of follicles is controlled by follicle stimulating hormone (FSH), which is what is measured by the follicle stimulating hormone (FSH) test. FSH is a critical reproductive hormone that is central to ovarian function and female fertility, and this is the reason that the FSH test is a standard part of fertility testing.
How to Test Egg Quality: Fertility Testing with the FSH and LH Blood Test
The FSH test is often considered a blood test for egg quality, though a number of others, including AMH test, are needed in addition to the FSH lab test for a complete picture of a woman’s fertility. The full fertility testing workup is what help us create a treatment plan that’s highly specific to each patient’s needs.
The level of FSH 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, and 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 test is performed as a combined FSH-LH test.
Because serum FSH test results depend on the point in a woman’s menstrual cycle, physicians have established a standard point in the menstrual cycle for performing the FSH fertility test. This is performed as a day 2 or day 3 blood test, meaning that you will need to have this test 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 FSH. 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 FSH test 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 FSH blood test results 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. FSH, like other hormone levels, changes 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 infertility treatment setting, leads to some younger patients with abnormal ovarian function for her age being missed.
FSH Test Normal Range: Is it Better to Have High or Low FSH?
What is the FSH blood test normal range? 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, and quality and quantity of eggs decline. In response, the pituitary gland works harder to produce more FSH to compensate. Therefore, a low number on your FSH test means that your ovaries are functioning well, while a high FSH levels signal diminished ovarian reserve (DOR).
FSH Test Results Normal Range by Age
As explained earlier, FSH lab test results naturally increase with age. At CHR, we have created a chart that summarizes normal FSH test ranges (as well as AMH hormone levels) by age. Using age-specific normal values for AMH and FSH tests enables our physicians to identify younger women with early stages of ovarian problems, as well as provide a more nuanced IVF prognosis to older women based on their ovarian function.
At CHR, we take into consideration a woman’s age when determining whether or not her FSH levels are in-range, as women naturally produce more FSH as they age.
Indicators of elevated FSH in females, or elevated FSH symptoms, include many of the symptoms typically associated with premature menopause-- irregular periods, hot flashes, and weight gain (among others). Women with FSH hormone function problems may have also been diagnosed with “unexplained infertility” in the past. At CHR, we perform exhaustive diagnostic testing to get to the root of every patient’s infertility problem.
Age Specific Baselines for FSH Test Result Interpretation
|FSH Test Normal Range|
|Age||(Day 3 Blood Test)||Average AMH|
|< 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 results, including the FSH test normal range interpreted against what’s normal at 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
The success of an in vitro fertilization (IVF) cycle depends largely on the patient's ability to produce a good number of high-quality eggs. In attempts to predict the probability of a patient’s IVF cycle being successful and before proceeding with treatment for high FSH, CHR’s medical team might run a number of tests to assess her ovarian reserve, including:
Antral follicle counts (AFCs), the number of small follicles at the start of a menstrual cycle, may be assessed with a transvaginal ultrasound, though at CHR we consider AFCs to be only a secondary measure of ovarian reserve.
What Do High FSH Levels Mean for IVF?
High FSH levels, as well as abnormally low AMH and/or AFCs, denote a relatively poor fertility prognosis and low probability of success with IVF. Learn more about interpreting your FSH levels.
Norbert Gleicher, MD, leads CHR’s clinical and research efforts as Medical Director and Chief Scientist. A world-renowned reproductive endocrinologist, 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.
Last Updated: February 5, 2019