A hostile environment: male infertility and pollutants
Breathing in air pollution in the form of fine particles produced by road traffic and construction and which hang in the air could increase the risk of male infertility by 25 per cent, a new study warns.
Published in the British Medical Journal (BMJ), the Danish study also found that women face a different threat with UK traffic noise levels, leading to a 14% increased risk of infertility.
Researchers analysed data on over 500,000 men and nearly 400,000 women in Denmark aged between 30 and 45 who had fewer than two children. They looked for patterns linking reproductive health and air and noise pollution prevalent in their location.
In terms of air pollution, the study’s authors specifically looked at PM2.5s. These are tiny particles, less than 2.5 micrometres in diameter, created by road traffic and the burning of fossil fuels.
Danish men exposed to an annual average of 2.9 micrograms of fine particles of pollution per cubic metre had a 24% increased risk of infertility. Yet, worryingly, levels in our UK cities are nearly double that figure.
Female fertility and pollutants
The study found that PM2.5 exposure did not have a similar effect on women’s fertility, but it did note that noise pollution had an impact. This is thought to be due to the link between noise pollution, increased stress and disturbed sleep patterns.
The research, published in the BMJ, is observational, meaning it cannot directly establish that pollution causes infertility. Lifestyle factors were not considered.
Professor Allan Pacey, an expert in andrology at the University of Manchester, commented on the study: “It is possible that the real cause of this association lies with something that it was not possible to measure.”
Lifestyle factors in male infertility
It is challenging to avoid exposure to environmental pollution, particularly if living and working in urban areas, but there are modifiable lifestyle factors that we know impact our overall health and, by extension, the health of our sperm.
Here are 7 lifestyle factors that could affect male fertility and sperm health:
- Smoking: smoking can impact sperm quality, by giving you a lower sperm count, poorer sperm movement and can affect your DNA fragmentation.
- Alcohol: we know that women are advised to abstain if they are trying to get pregnant, but is there a ‘safe’ amount for men? A 2023 meta-analysis of 40 studies found alcohol intake reduced semen volume during each ejaculation.
- Steroid use: anabolic steroids are recognised as one of the causes of male infertility. Even things like testosterone supplements can act as a male contraceptive, and it may take some time to reverse their effects.
- Stress: chronic stress can cause hormonal imbalances within the body, affecting sperm production.
- Lack of sleep: research has found a lack of sleep may be a factor in male infertility. A study published in Fertility & Sterility, which followed almost 700 couples for a year, found that men who slept less than 6 hours a night were 31% less likely to get their partner pregnant.
- Being overweight: having a too high BMI is associated with many different health risks, and it is recognised as a common cause of male infertility. Studies show that it can affect hormone levels, causing reduced sperm production, and there may also be a link between obesity and reduced sperm motility and morphology.
- Poor diet: good nutrition supports all our bodily functions, including producing healthy sperm. Diets high in processed meat, caffeine, saturated fatty acids and trans fats are linked to low-quality semen. Conversely, antioxidant-rich diets are linked to better sperm quality.
Male infertility affects up to half of couples having problems starting a family. Our Male Fertility MOT test will check your sperm count, shape, movement, and other characteristics and help diagnose and treat male infertility causes.
