What Hormones Are Tested for Female Fertility?

More than likely, you’ve seen posts on social media telling women to test their hormones, but they never say which hormones to test. In this post, we’ll explore the key hormones that are tested for female fertility, what they indicate, and why they’re important.  

Fertility is a complex interplay of biological systems, and hormones play a critical role in a woman’s ability to conceive. If you're having difficulty getting pregnant or are preparing for fertility treatments like IVF, your doctor may recommend testing certain hormones to assess your reproductive health. These tests provide valuable insights into ovarian function, egg quality, and your overall fertility potential.  

1. Follicle-Stimulating Hormone (FSH) 

• What It Is: FSH is produced by the pituitary gland and plays a key role in regulating the menstrual cycle. It stimulates the growth of ovarian follicles, which house and mature eggs in the ovaries. 

• Why It’s Important: FSH levels are typically tested on day 3 of your menstrual cycle to assess ovarian reserve—the quantity of eggs remaining in your ovaries. High FSH levels can indicate a diminished ovarian reserve, suggesting that the ovaries may not be responding optimally to stimulation. Low FSH levels, on the other hand, may suggest that the ovaries are not properly functioning or that other hormonal imbalances are at play. 

• Normal Range: For women of reproductive age, a typical FSH level is between 3 and 10 mIU/mL on day 3 of the cycle. Higher levels (above 10) may indicate a fertility issue. 

2. Luteinizing Hormone (LH) 

• What It Is: LH is another hormone produced by the pituitary gland that triggers ovulation—the release of a mature egg from the ovary. 

• Why It’s Important: LH levels are also tested on day 3 of the menstrual cycle, and a high LH level may indicate conditions like Polycystic Ovary Syndrome (PCOS), which can interfere with ovulation. LH levels surge just before ovulation, which is why LH tests are also used to predict ovulation in fertility tracking. 

• Normal Range: On day 3, LH levels should be close to FSH levels (generally between 5 and 20 mIU/mL). A significant imbalance between FSH and LH can signal potential issues with ovulation. 

3. Estradiol (E2) 

• What It Is: Estradiol is the primary form of estrogen in the body, produced by the ovaries. It regulates the menstrual cycle and is critical for maintaining the uterine lining, preparing it for potential implantation of an embryo. 

• Why It’s Important: Estradiol levels are typically tested on day 3 along with FSH and LH. Elevated estradiol levels on day 3 can sometimes mask a high FSH level, making it appear as though ovarian reserve is better than it actually is. High estradiol levels may also be a sign of a follicle cyst, which can interfere with normal ovulation. 

• Normal Range: On day 3, estradiol levels should be below 80 pg/mL. Higher levels can indicate diminished ovarian reserve or other issues affecting fertility. 

4. Anti-Müllerian Hormone (AMH) 

• What It Is: AMH is produced by the small, developing follicles in the ovaries. It is considered one of the most reliable indicators of ovarian reserve. 

• Why It’s Important: Unlike FSH, AMH levels remain fairly stable throughout the menstrual cycle, making it a reliable test to measure ovarian reserve at any time. Higher AMH levels suggest a greater number of eggs, while lower levels may indicate a reduced ovarian reserve. However, very high AMH levels are often associated with conditions like PCOS. 

• Normal Range: AMH levels typically range from 1.0 to 4.0 ng/mL. Lower levels (below 1.0) suggest a reduced egg supply, while higher levels (above 4.0) may indicate PCOS. 

5. Progesterone 

• What It Is: Progesterone is a hormone produced by the corpus luteum after ovulation. Its primary role is to prepare the uterine lining for a potential pregnancy and maintain early pregnancy if conception occurs. 

• Why It’s Important: Progesterone levels are often tested during the second half of the menstrual cycle (around day 21 in a 28-day cycle) to confirm whether ovulation has occurred. Low progesterone levels during this phase may indicate that ovulation has not occurred or that the body is not producing enough progesterone to support a pregnancy. 

• Normal Range: Mid-luteal phase progesterone levels (7 days after ovulation) should be above 5 ng/mL. Levels below this threshold may indicate problems with ovulation or a luteal phase defect. 

6. Prolactin 

• What It Is: Prolactin is a hormone produced by the pituitary gland that stimulates milk production after childbirth. 

• Why It’s Important: High prolactin levels can interfere with ovulation and menstrual regularity. Elevated prolactin (a condition known as hyperprolactinemia) may lead to irregular periods or even an absence of ovulation, making conception difficult. Elevated prolactin levels can be caused by certain medications, stress, or benign pituitary tumors. 

• Normal Range: For women of reproductive age, prolactin levels typically range from 5 to 27 ng/mL. Higher levels may warrant further investigation. 

7. Thyroid-Stimulating Hormone (TSH) 

• What It Is: TSH is produced by the pituitary gland and regulates the function of the thyroid, which in turn controls metabolism and various reproductive processes. 

• Why It’s Important: Thyroid imbalances can affect menstrual cycles and ovulation. Hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can both impact fertility by disrupting hormone balance. 

• Normal Range: Optimal TSH levels for fertility are generally considered to be between 0.4 and 4.0 mIU/L. Levels outside this range may indicate a thyroid disorder that could affect fertility. 

Conclusion 

Hormonal imbalances are a key factor in many fertility issues, and testing for these hormones is an important step in diagnosing and treating infertility. By understanding what each hormone indicates and how it affects fertility, you can gain valuable insights into your reproductive health and work with your doctor to develop an effective treatment plan. 

If you're struggling to conceive, schedule a consultation with one of our board-certified fertility specialists to talk about these tests to ensure you're taking the right steps toward parenthood.