Skip to main content
January 24, 2019

The main causes of infertility in men

This month it is all about the Road to Baby. Fertility expert Dr Wanjiru Ndegwa and I have looked at the main causes of infertility in women and last week she answered some of your questions. If you have more, please send them to [email protected]

This week, we look at the main causes of infertility in men and I spoke to Dr Mburugu, a urologist based at Aga Khan Hospital in Parklands, Nairobi. He says there are two types of infertility in men: non-obstructive and obstructive.


With non-obstructive infertility, a man produces the normal amount of semen (2-5ml] but it has little of no sperm in it. Alternatively, the ejaculate may have sperm but it is impaired or abnormal so that it does not move fast enough; or the sperm count is very low so that chances of one sperm making it to the egg and fertilising it are drastically reduced.


1. Sexually Transmitted Infections – chlamydia and gonorrhoea are the main culprits here because they are sometimes asymptomatic. These infections can go unnoticed and cause scarring that blocks a man’s epididymis or vas deferens so that sperm though produced cannot reach the penis and ultimately the woman’s cervix during intercourse. This can be solved through assisted fertilisation.

Genital tuberculosis can also block these tiny tubes and hinder movement of sperm.

2. About 10 to 30 per cent of boys with mumps will have their testes affected. Unfortunately, there is very little a doctor can do here.

3. Injuries like a twisted testicle can cause infertility if they go untreated for more than six hours. Any swelling or acute pain in the testes should be treated immediately.

Anything that affects the cardiovascular system will affect a man’s sexual performance and, by extension, his fertility. Clogged arteries from a very fatty diet, diabetes, high blood pressure, these all affect a man’s ability to raise and maintain an erection which is mandatory for the delivery of sperm into a woman’s vagina during intercourse. Cigarette smoking, high alcohol intake and a lack of exercise all contribute to poor cardiovascular health which makes it difficult for the penis to fill up with blood and get hard.

Testicles hang outside of the body cavity because the ultimate temperature for sperm production is lower than that of the rest of the body. Heat is not a friend to sperm production so tight underwear, saunas and sitting for long periods of time are not advised if you and your partner are trying to conceive.

A large waistline will not only make you less attractive to women, but that abdominal fat will actually convert the male hormone testosterone to oestrogen, decreasing your libido and even making you depressed.

Good luck in your baby making, and yes, I agree Valentine is a strong name for a girl and a lovely one for a boy.

Poll of the day