Basics of Male Fertility

Understanding how male fertility works provides important context for the assessment and management of reproductive health. Male fertility depends on the normal structure and function of the male reproductive system and the successful production, maturation and transport of sperm.

The male reproductive system is made up of a group of organs that make up the reproductive system and urinary system. Some of these organs include :

• External organs (e.g. testes, scrotum, penis), and
• Internal organs (e.g. vas deferens, prostate, and urethra).

The primary functions of the male reproductive system are :

• To produce, maintain and transport sperm cells and semen,
• To discharge sperm externally, and
• To produce and secrete male sex hormones, like testosterone.

The position of the testes outside the body maintains a cooler temperature than the body, which is essential for normal sperm development.

Sperm development (spermatogenesis) takes place in the seminiferous tubules of the testes and is regulated by hormones from the brain:

• Follicle-stimulating hormone (FSH): stimulates sperm production
• Luteinizing hormone (LH): stimulates testosterone production

The process of producing fully developed, motile sperm takes approximately 70 days. After formation, sperm undergo maturation in the epididymis, where they gain the ability to swim and fertilise an egg.

During ejaculation, mature sperm exit the epididymis and travel through the vas deferens. Fluids from the seminal vesicles and prostate gland mix with sperm to form semen, the fluid expelled during ejaculation. 

Male factor infertility contributes to a significant proportion of infertility cases, either alone or in combination with female factors. A clear understanding of how sperm are produced and transported helps explain why certain evaluations and treatments are necessary when fertility issues arise.