Problems with sperm production
The most common causes of male infertility are called:
- Azoospermia, no sperm cells are produced
- Oligospermia, where few sperm cells are produced
- Teratospermia, where a high proportion of sperm is abnormally shaped
Sometimes, sperm cells are malformed or die before they can reach the egg. In rare cases, a genetic disease such as cystic fibrosis or a chromosomal abnormality can cause male infertility.
Around one in three cases of male infertility are caused by blockages or absence of tubes which prevent sperm passage. This could be caused by injury, genetic abnormality, or a vasectomy.
It is usually a good sign if you have ever conceived a baby with any partner in the past, but this may not mean that your sperm is compatible with your current partner.
Other factors that adversely affect sperm quality and numbers include:
- Smoking
- Excessive drinking
- Drugs, including steroids and recreational use
- Weight and Body Mass Index (BMI)
- Frequent exposure to extreme heat (working in hot temperatures, or regular saunas)
- Working in cramped conditions (for example, truck drivers)
- Acute viral illness
- Operations for undescended testes or hernias
