Testosterone is essential for both initiating and maintaining spermatogenesis. Its production depends on the pituitary gland, a small structure at the base of the brain that releases two key hormones:  

- Luteinizing hormone (LH) → stimulates Leydig cells in the testes to produce testosterone.  

- Follicle-stimulating hormone (FSH) → acts on Sertoli cells to support optimal sperm production.  

Beyond Sperm Production: Other Roles of Testosterone  

Testosterone also plays a crucial role in:  

- Development of male external genitalia during fetal life.  

- Muscle growth and strength.  

- Libido and erectile function.  

How Does Testosterone Change With Age?  

As men age, testosterone levels gradually decline, leading to a range of symptoms known as andropause. While the number of sperm does not significantly decrease, the quality of sperm declines, which can:  

- Reduce fertility.  

- Increase the risk of genetic abnormalities in offspring.