Endocrinology in Fertility: The Hormonal Foundation of Reproduction
Endocrinology is the branch of medicine that focuses on the body’s hormonal system — the glands and hormones that regulate key functions such as growth, metabolism, and reproduction.
In fertility care, endocrinology plays a critical role in understanding and managing the hormonal balance needed for
- Ovulation
- Menstrual cycles
- Egg and sperm production
- Embryo implantation
- Pregnancy maintenance
Key Hormones in Reproduction
| Hormone | Function |
|---|---|
| FSH (Follicle-Stimulating Hormone) | Stimulates the ovaries to grow follicles (eggs) |
| LH (Luteinizing Hormone) | Triggers ovulation and supports corpus luteum |
| Estradiol (E2) | Helps grow the uterine lining and regulates FSH |
| Progesterone | Prepares and supports the uterine lining after ovulation |
| AMH (Anti-Müllerian Hormone) | Reflects ovarian reserve (egg supply) |
| Prolactin | High levels can interfere with ovulation |
| TSH (Thyroid-Stimulating Hormone) | Thyroid imbalance can affect cycles and pregnancy |
| Insulin | Elevated levels (e.g., in PCOS) affect ovulation and egg quality |
Common Endocrine Conditions That Affect Fertility
- Polycystic Ovary Syndrome (PCOS)
A hormonal imbalance causing irregular cycles, high androgens, and anovulation. - Thyroid Disorders (Hypo- or Hyperthyroidism)
Disrupt normal menstrual cycles, ovulation, and can increase miscarriage risk. - Hyperprolactinemia
Elevated prolactin levels that suppress ovulation. - Adrenal Disorders
Can disrupt the hormonal environment for ovulation and embryo implantation. - Diminished Ovarian Reserve
Low AMH or high FSH levels signal reduced egg supply and hormonal changes.
The Role of a Reproductive Endocrinologist
A Reproductive Endocrinologist is a fertility specialist trained to diagnose and treat hormonal imbalances affecting fertility in both women and men. They:
- Interpret hormone blood tests
- Regulate ovulation and cycle timing
- Customize IVF or IUI protocols
- Treat hormonal disorders (e.g., PCOS, thyroid disease)
- Support early pregnancy with hormone monitoring
Hormone Testing in Fertility Treatment
Hormonal testing may be done to:
- Assess egg reserve (AMH, FSH, Estradiol)
- Track ovulation (LH surge, progesterone)
- Evaluate thyroid and prolactin levels
- Guide medication dosages in IVF/IUI
When to See an Endocrinology Specialist
You may need endocrinology-focused fertility care if you have
- Irregular or absent periods
- Difficulty ovulating
- Recurrent miscarriages
- Hormonal imbalances (e.g., PCOS, thyroid, elevated prolactin)
- Abnormal fertility hormone levels on bloodwork