Understanding male fertility

Male fertility refers to a man's ability to cause pregnancy in a fertile female. It depends on the quantity and quality of sperm, which are produced in the testes and released during ejaculation.

1. 1

   Day 1–74: Spermatogenesis

   Immature cells in the seminiferous tubules of the testes develop into mature sperm cells over 74 days. Hormones, testosterone, FSH, and LH, regulate the whole process. Lifestyle changes made today affect the sperm produced in three months.

2. 2

   Maturation in the epididymis

   After production, sperm travel through the epididymis, a coiled tube behind each testis, where they gain the ability to swim and become capable of fertilisation. This maturation phase takes about 12 days.

3. 3

   Ejaculation: the fertilisation window

   During ejaculation, sperm mix with fluid from the seminal vesicles and prostate to form semen. A healthy ejaculate contains 16 million or more sperm per ml (WHO 2021 reference range). Only one is needed to fertilise an egg, but sperm quality across count, motility, and morphology all affect the odds.

If you and your partner have been trying to conceive for 12 months without success (or 6 months if your partner is over 36), the male-factor workup belongs on the table at the same time as the female-side investigations, not after.