Key Reproductive Hormones

Reproductive hormones play a vital role in human anatomy and physiology, influencing everything from growth and development to fertility and pregnancy. Understanding these hormones helps us grasp how the body regulates reproductive functions and maintains overall health.

1. Gonadotropin-releasing hormone (GnRH)

   • Secreted by the hypothalamus, it stimulates the anterior pituitary gland.
   • Regulates the release of FSH and LH, crucial for reproductive function.
   • Pulsatile release is essential for normal reproductive hormone levels.

2. Follicle-stimulating hormone (FSH)

   • Produced by the anterior pituitary, it promotes the growth of ovarian follicles in females.
   • In males, it stimulates spermatogenesis in the testes.
   • Works in conjunction with LH to regulate the menstrual cycle and fertility.

3. Luteinizing hormone (LH)

   • Also produced by the anterior pituitary, it triggers ovulation in females.
   • Stimulates testosterone production in males.
   • Plays a key role in the regulation of the menstrual cycle and reproductive health.

4. Estrogen

   • Primarily produced in the ovaries, it is vital for the development of female secondary sexual characteristics.
   • Regulates the menstrual cycle and prepares the uterus for pregnancy.
   • Influences bone density, cardiovascular health, and mood.

5. Progesterone

   • Secreted by the corpus luteum in the ovaries, it prepares the endometrium for implantation.
   • Maintains pregnancy by inhibiting uterine contractions.
   • Plays a role in the menstrual cycle and breast development.

6. Testosterone

   • Produced mainly in the testes, it is essential for the development of male secondary sexual characteristics.
   • Regulates libido, muscle mass, and bone density.
   • Influences spermatogenesis and overall male reproductive health.

7. Inhibin

   • Secreted by the gonads, it inhibits the production of FSH from the anterior pituitary.
   • Helps regulate sperm production in males and follicle development in females.
   • Plays a role in feedback mechanisms to maintain hormonal balance.

8. Prolactin

   • Produced by the anterior pituitary, it stimulates milk production in breastfeeding women.
   • Influences reproductive health and menstrual cycle regulation.
   • Levels can be affected by stress, sleep, and other hormones.

9. Oxytocin

   • Secreted by the posterior pituitary, it stimulates uterine contractions during labor.
   • Plays a role in milk ejection during breastfeeding.
   • Involved in social bonding and emotional responses.

10. Human chorionic gonadotropin (hCG)

    • Produced by the placenta during pregnancy, it supports the corpus luteum.
    • Maintains progesterone production in early pregnancy.
    • Commonly used in pregnancy tests to detect early pregnancy.