Male infertility factor accounts for 50% of all fertility problems and the reason can often be due to oxidative stress. Sperm naturally produces small amounts of free oxygen radicals known as ROS, and this small amount is required for normal sperm function and good sperm health.


However the finite balance of ROS production can be disturbed, causing levels of ROS to increase and oxidative stress to occur. Oxidative stress leads to sperm damage, therefore affecting normal fertility.

25-40% of infertile men have high levels of ROS and therefore reduced antioxidant capacity. This causes male infertility factor by producing poor sperm motility and vitality, abnormal sperm shape (morphology) and a low sperm count. However ROS levels can also be elevated in a man with a normal sperm analysis result.

ROS also causes sperm DNA fragmentation and is correlated with an increase in time to pregnancy when trying to conceive naturally, implantation failure and reduced IVF pregnancy rates.

What causes oxidative stress?

There are many cause of oxidative stress including:

• Infection
• Prostatitis
• Varicocele
• Previous surgery
• Undescended testes
• Chronic disease
• Certain medication
• Lifestyle such as smoking, drugs, alcohol consumption, poor diet
• Excessive heat to the testicle region
• Exposure to toxins

ROS Testing:

Before considering ROS testing for a man with male infertility factor it is important to get a semen analysis done. If the parameters of the test are abnormal and particularly if vitality is poor then a ROS test may be indicated. Currently in the UK, ROS testing is only available privately and cost in the region of £125. You can find out more here.


The first step in reducing ROS in a man with male infertility factor should be to concentrate on improving lifestyle factors, in particular stopping smoking, reducing alcohol and eating healthily. A diet rich in anti-oxidants can protect against oxidative stress.

Research has shown that anti-oxidant supplements can reduce ROS levels. However these should only be taken if the semen parameters are abnormal, as discussed above a little ROS is essential for normal sperm function.

Any infection should be treated and surgical repair of for example a varicocele considered.

It may be necessary to consider occupational hazards such as working with toxic substances or working for sustained periods in a hot environment.
You can find out more about sperm health and the testing and treatment available here .

Male Infertility - Oxidative stress