Understanding Your Body: Hormones and Their Impact on Fertility

By Dr. Suman Lal, Senior Director & Unit Head – Obstetrics & Gynaecology

Hormones control fertility and everything from ovulation and periods to mood and energy. Understanding how hormones affect fertility can empower you to make informed choices about your reproductive health.

Here’s a breakdown of key hormones and how they impact your body’s ability to conceive.

1. Estrogen

Estrogen is often referred to as the female sex hormone and is crucial for fertility. Produced mainly in the ovaries, estrogen regulates the menstrual cycle, thickens the uterine lining for implantation and triggers ovulation – the release of an egg from the ovary. Balanced estrogen levels are key to regular cycles; low levels cause irregular periods making conception tricky and high levels can indicate PCOS (polycystic ovary syndrome) which can also impact fertility.

2. Progesterone: The Pregnancy Hormone

Progesterone is key to getting the body ready for pregnancy. After ovulation the ruptured follicle that released the egg turns into a structure called the corpus luteum which produces progesterone. This hormone stabilizes the uterine lining creating an environment for an embryo to implant. If conception doesn’t occur progesterone levels drop and menstruation occurs. Low progesterone levels can interfere with implantation or cause early pregnancy loss so it’s important for fertility and sustaining a pregnancy.

3. Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH)

LH and FSH are released by the pituitary gland and are part of the ovulation process. FSH stimulates follicle growth in the ovaries and LH triggers the release of the mature egg. LH surges 24-36 hours before ovulation which is why ovulation prediction kits often track LH levels to identify fertile windows. Imbalances in these hormones can disrupt ovulation and make it harder to conceive.

4. Testosterone in Both Genders

Though often linked to male health, testosterone is also important in females. In women testosterone contributes to follicle development and libido both of which are key for fertility. In men testosterone is key for sperm production. Hormonal imbalances such as low testosterone in men or excess testosterone in women (often due to PCOS) can impact fertility for both.

5. Thyroid Hormones and Fertility

Thyroid hormones regulate metabolism but also impact reproductive health. Conditions like hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid) can disrupt menstrual cycles and cause irregular ovulation. Proper thyroid function is essential for a stable hormonal environment which supports conception and early pregnancy.

6. Prolactin and Ovulation

Prolactin, a hormone involved in milk production after pregnancy, can affect ovulation when levels are high. High prolactin levels can suppress ovulation making it harder to conceive. In these cases addressing prolactin levels with medical guidance can help restore fertility.

Conclusion

Hormones are finely tuned and interconnected in the reproductive system. Imbalances in any one of these hormones can cause conception or pregnancy difficulties. Understanding the role of estrogen, progesterone, LH, FSH, testosterone, thyroid hormones and prolactin in fertility can help you identify potential issues early and seek support when needed. By tracking your cycles, symptoms and consulting with healthcare providers you can take control of your reproductive health and increase your chances of conception.