Problems with sperm

Sperm are extremely vulnerable cells. They take seven weeks to form and can be affected by outside influences at any point in their development. Because of this, it's entirely possible for a man to give sperm samples on separate occasions that differ widely both in quality and quantity.

Testicular and sperm failure

The cause of this is usually hard to establish, but it may be due to a chromosomal problem such as Klinefelter's syndrome (when a man has two or more X chromosomes rather than one), testes that did not descend properly after birth, a blow to the testes, such as a sports injury, or the man having suffered mumps as an adult.

Low sperm counts

By itself, a low sperm count does not mean infertility. Many men with low sperm counts father children, but conception tends to take longer. Unfortunately, when there are few sperm the majority tend to be abnormal or are not very active. Low sperm counts and sperm abnormalities may be caused by hormonal, anatomical, or immunological problems, or even environmental factors.

Male fertility is checked by two sperm tests, which also look for any sperm abnormalities. Each millilitre of semen should contain at least 20 million sperm, most of which should be normal.

If there are fewer than 20 million sperm per millilitre or there's a high proportion of abnormal sperm, the semen is rated poor.

Workplace hazards

Working with harmful substances can be particularly dangerous for a man's fertility, as some of them can lower the sperm count.

At your first consultation, tell your doctor if you work with any of the following substances: