The man’s contribution to reproduction

Sperm production: the foundation of male reproduction

In the female body, all the eggs are already present in the ovaries, where they mature cyclically. In the male, however, production of sperm cells begins only with the onset of sexual maturity – it is during puberty that sperm cells form in the testes for the first time. In healthy men, this process continues until death.
Just like egg maturation in the woman, sperm formation is controlled by the sex hormones FSH (follicle-stimulating hormone) and LH (luteinising hormone). Hormonal signals from the pituitary gland trigger distribution of the sex hormones, whereby FSH is responsible for the formation and maturation of sperm cells and LH is responsible for the production of the sex hormone testosterone, which – among other things – controls the formation of secondary sexual characteristics and the sex drive.

Sperm formation and maturation of sperm

With the onset of sexual maturity, millions of sperm cells are produced in the seminiferous tubules of the testes every day. The sperm cells remain in the testes for approximately 10 weeks, after which they pass into the epididymides, where they continue to mature. In the epididymides the sperm cells acquire their ability to move, or motility. After about 12 weeks, sperm formation is complete – healthy sperm now have a fully formed head that contains the male genetic make-up, a central part that generates kinetic energy and a tail that drives and controls the sperm cell.

Male reproductive physiology

During sexual intercourse, the mobile sperm cells are squeezed out through muscle contractions with ejaculation via the seminal ducts and the urethra. The motile sperm cells travel through the vagina, the cervix and the uterus to the fallopian tubes. If there is a mature egg in the fallopian tube, the sperm cells try to penetrate the wall of the egg cell and become embedded inside the egg – which is then fertilized. Many sperm cells don’t make it to the fallopian tubes, which is why a single ejaculation contains 300-400 million sperm cells. If the quantity of sperm cells is significantly below this average or if the sperm cells in the ejaculate do not have sufficient motility, this can affect the man’s reproductive capacity.

What factors are decisive for sperm motility?

The reasons why a couple fails to fall pregnant can lie with either the man or the woman, or both partners. The most common reason for infertility in the man is insufficient production of normally shaped, motile sperm cells. According to the guidelines of the WHO, “normal” sperm motility is defined by the following values:

• amount of ejaculate: 2 ml or more
• pH-value of the ejaculate: 7.2 or more
• total number of sperm cells in the ejaculate: at least 40 million sperm cells
• sperm concentration: at least 20 million sperm/ml
• morphology of the sperm: at least 15% normally formed
• sperm motility: at least 50% with forward movement or 25% with progressive movement within 60 min. after ejaculation

We establish the details of sperm production and quality with a sperm analysis performed in our labs. Based on the results of the sperm analysis, we then advise you concerning further diagnosis and treatment methods.