FSH Levels by Age - Follicle Stimulating Hormone Levels with Chart
What is a normal FSH level to get pregnant? When it comes to FSH levels and fertility, it’s important to recognize that there is no one normal FSH level for all women. What is normal is that the normal range depends on a woman’s age. As women get older, FSH levels rise, until they reach a level of 40 mIU/mL or higher during menopause. The chart further down this page can help you understand what FSH level is normal for you, based on your age.
What is FSH?
FSH is a hormone released by the pituitary gland, which is located on the underside of the brain. A blood test to measure FSH levels is a common part of any infertility workup. An FSH blood test detects the level of this hormone in the blood to check whether a woman’s levels are normal. This information is then used as an indicator for ovarian function.
Lower FSH levels are generally associated with better ovarian function, while higher FSH levels are associated with diminished ovarian reserve. Most women have low FSH levels in their 20s, and FSH increases as a woman ages.
Interpreting Your FSH Levels: What FSH Level is Normal for You?
About a decade ago, CHR's research established references for AMH and FSH levels by age. Any FSH level means something different depending on a woman’s age. For example, a normal FSH level for a woman at 42 suggests premature ovarian aging (POA) if found in a 30-year old. To really assess a woman's ovarian reserve and her IVF pregnancy chances, we need to look at age-specific AMH and FSH levels. The AMH and FSH levels chart below demonstrates age-specific AMH and FSH levels among CHR's patients.
What is a Normal FSH Level? FSH Level Chart by Age
FSH levels naturally rise as women get older. The FSH levels chart below shows the normal range (along with AMH levels) by female age. As the table demonstrates, normal FSH levels go from below 7.0 mIU/mL for someone younger than 33 to over 8.5 mIU/mL for a woman over 41. This chart is an important tool that we use to create tailored fertility treatment plans for our patients.
Age Specific Baseline FSH and AMH Levels by Age
|Normal FSH Levels|
|Age||(Day 3 of the Menstrual Cycle)||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|
"CHR developed and uses an age-based AMH and FSH scale, which is more accurate at predicting pregnancy chances."Dr. Norbert Gleicher
Many fertility centers, unfortunately, still use universal cut-off values for a normal FSH range. This can mean that younger women with POA and resulting higher FSH levels for their age (but within normal range based on a universal “normal” value) are given inappropriate fertility treatment or misdiagnosed as “unexplained infertility.
When a patient has high FSH, some of these centers also refuse to provide treatment, irrespective of patient age and other factors. Or these centers may push women to egg donation (prematurely, in our opinion). This approach may ensure higher pregnancy rates at such centers (because they reject women with lower chances of pregnancy), but it leaves women with elevated FSH (and/or low AMH) abandoned, without access to treatment that can be quite successful if done correctly.
CHR does not use such arbitrary cut-off values. We look at follicle stimulating hormone range in the context of a woman’s age and other factors. This way, our physicians are able to individualize fertility treatments for each woman’s level of ovarian function. This is why we have so many patient with stories of successful pregnancy with their own eggs!
The graph you see on this page provides a visual representation of age-specific FSH levels, along with AMH level, as they change over a woman’s reproductive lifetime.
AMH May Be More Useful than FSH
What makes the “universal FSH cut-off” approach even more problematic is the fact that the most up-to-date medical literature suggests that FSH is not as specific as it was once thought. A number of papers published by CHR's physicians suggest that AMH is actually more specific than FSH in assessing ovarian reserve and pregnancy chances with IVF. Better AMH specificity makes sense because AMH reflects the smaller follicles, which represent a majority of a woman's ovarian reserve. (The figure above demonstrates that normal AMH ranges are narrower than normal FSH ranges, suggesting that AMH is more precise in reflecting ovarian reserve.) Given the superiority of AMH, IVF treatment decisions based on the FSH level alone, appears outdated.
While tests to check AMH and FSH levels are important in assessing ovarian reserve, both have limitations. Neither result can, indeed, categorically determine whether a woman can or cannot conceive, unless she has very high FSH levels. In addition, women can get pregnant with IVF even when AMH is completely undetectable, as over 50 pregnancies established so far at CHR in women with undetectable AMH levels clearly demonstrate. Therefore, placing too much emphasis on high FSH and low AMH can be misleading. It can also be harmful, as some physicians make patients wait for low FSH levels to magically appear in the next blood test before starting an IVF cycle--a practice that wastes precious time and makes no physiological sense.
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 6, 2019