What Hormones Do Blood Tests Measure and What Do They Mean?

Boston IVF fertility specialist Sara Arian, MD, FACOG, MSc, joins Progyny to explain the basics of infertility blood tests and outline what different fertility hormones —Follicle-Stimulating Hormone (FSH), Estradiol (E2), Luteinizing Hormone (LH), Anti-Müllerian Hormone (AMH), Serum Progesterone, Prolactin, Androgen—  indicate.

When evaluating an individual with ovaries' fertility, blood tests play a critical role in assessing reproductive potential and guiding treatment options. 

Why Are Blood Tests Important for Fertility?
Blood tests provide valuable insight into ovarian reserve, ovulation timing, and overall reproductive health. By measuring hormone levels, fertility specialists can determine how well the ovaries are functioning and recommend the best course of treatment.

Key Fertility Hormones and What They Reveal

• Follicle-Stimulating Hormone (FSH)
  
  • FSH is produced by the pituitary gland and is responsible for stimulating ovarian follicles to grow. It plays a key role in the early phase of the menstrual cycle, prompting the development of eggs.
  • Higher FSH levels may indicate diminished ovarian reserve.
  • Lower levels can be associated with irregular ovulation.
• Estradiol (Estrogen)
  
  • Estradiol is a form of estrogen secreted by the ovaries as follicles mature. Measuring estradiol levels helps determine:
    • The maturity of ovarian follicles
    • Ovulation timing
    • Response to fertility medications in IVF cycles
• Luteinizing Hormone (LH)
  
  • LH is another pituitary hormone that plays a major role in ovulation.
  • A surge in LH levels triggers ovulation.
  • Tracking LH can help determine the best time for conception or for scheduling fertility treatments like intrauterine insemination (IUI) or egg retrieval in IVF.
• Anti-Müllerian Hormone (AMH)
  
  • AMH is a key marker of ovarian reserve, as it is secreted by the small follicles in the ovaries.
  • Higher AMH levels suggest a greater egg supply, which is beneficial for fertility treatment.
    Lower levels may indicate a decline in ovarian reserve, which can impact reproductive planning.
• Progesterone
  
  • Progesterone is essential for maintaining pregnancy and preparing the uterine lining for embryo implantation.
  • Low levels may indicate issues with ovulation or implantation.
    In fertility treatments, progesterone supplementation is often used to support early pregnancy.
• Prolactin
  
  • Prolactin, produced by the pituitary gland, is primarily associated with breastfeeding but also impacts fertility.
  • Elevated prolactin levels can disrupt ovulation and menstrual cycles, leading to infertility.
• Androgens (Testosterone, DHEA-S)
  
  • Androgens, or male hormones, are present in individuals in small amounts and are produced by the ovaries and adrenal glands.
  • Elevated androgen levels are commonly seen in polycystic ovary syndrome (PCOS), which can impact ovulation and cause symptoms like acne and excess hair growth.

How These Tests Guide Fertility Treatment
Understanding these hormone levels allows fertility specialists to create personalized treatment plans. For example:

• If FSH and AMH indicate low ovarian reserve, IVF with egg retrieval may be recommended sooner.
• If LH tracking shows irregular ovulation, ovulation induction medications may help.
• If prolactin levels are elevated, medication may be needed to restore ovulation.

Taking the Next Steps
If you're trying to conceive or want to understand your fertility potential, hormone testing can provide clarity and direction. Schedule a consultation with Boston IVF to discuss fertility testing and personalized treatment options to help you on your journey to parenthood.