Understanding FSH Levels and What They Mean for Fertility

Follicle Stimulating Hormone (FSH) plays a key role in female fertility—and testing your FSH level is often one of the first steps in understanding your ovarian function. Typically measured through a blood test (not urine), FSH is evaluated alongside other hormones during a fertility workup to assess ovarian reserve.

Why does FSH matter?

Lower FSH levels generally suggest healthier ovarian function, while higher levels can indicate diminished ovarian reserve (DOR), making conception more difficult. FSH naturally increases with age, which is why it's commonly included in both clinical and at-home fertility assessments, particularly for women over 35. However, interpreting FSH levels accurately requires more than a one-size-fits-all approach.

The Problem with “Universal” FSH Ranges

Many fertility centers, unfortunately, still use universal FSH cut-off values—the same thresholds for all patients, regardless of age. This can lead to misdiagnoses and inappropriate treatment recommendations. For example, a younger woman with elevated FSH for her age (a possible sign of premature ovarian aging, or POA) may be told her results are “normal” based on these outdated cutoffs and classified as having “unexplained infertility.”

In more extreme cases, fertility centers may refuse to treat women with high FSH altogether, or pressure them to use donor eggs—often prematurely. While this may protect clinic success rates by avoiding lower-prognosis patients, it leaves many women without access to IVF using their own eggs, even when a carefully individualized protocol could lead to success. At CHR, we take a different approach. 

CHR’s Age-Specific, Evidence-Based Approach

At CHR, we’ve spent decades studying age-specific hormone levels and developing customized treatment plans based on a patient’s biological reality—not arbitrary cutoffs. We were among the first to publish reference ranges for FSH and AMH by age, a critical advancement that allows for better diagnosis and personalized care.

For example, a level of 8.0 mIU/mL might be completely normal for a woman over 40, but would raise concerns for someone in her early 30s. This distinction matters—not just for understanding your fertility, but for making the right treatment decisions at the right time.

Time is also critical in cases of elevated FSH. That’s why CHR remains open 7 days a week 365 days a year. Our commitment to personalized care is why many of our patients with high FSH and low AMH have gone on to conceive successfully using their own eggs.

FSH Is Not the Full Story

What makes the reliance on universal FSH thresholds even more problematic is that FSH alone is not a definitive measure of fertility. The most current literature—including several studies published by CHR physicians—shows that AMH (Anti-Müllerian Hormone) is often a more specific marker of ovarian reserve. AMH reflects the number of small, resting follicles in the ovaries—offering a more accurate snapshot of reproductive potential than FSH alone.

Still, even AMH has its limitations. No single hormone can determine with certainty whether a woman can or cannot conceive—unless FSH is extremely elevated. Unfortunately, some physicians place too much weight on a single hormone test, advising women to delay IVF treatment until their FSH drops. This not only lacks scientific validity—it wastes valuable time that many patients can’t afford to lose.

The Bottom Line

Hormone tests like FSH and AMH are valuable tools—but only when interpreted in the right clinical and situational context. At CHR, we tailor every protocol to each woman’s unique biology, using age-specific hormone ranges, in-depth diagnostics, and years of experience treating women other clinics may turn away.

If you’ve been told you’re out of options—or simply want a second opinion—you’re not alone. Contact CHR to learn more  about how we can help you take the next step, with science and compassion on your side.