An international team of scientists has published alarming data showing that sperm counts have halved worldwide in the past 50 years and that the trend was accelerating.
The decline, warned Professors Hagai Levine and Shanna Swan, could become too big a problem to ignore, with the potential to "threaten the survival of humanity".
Sperm count is important, but it's not everything. When a man goes for a fertility check and does a sperm analysis, three key parameters are looked at: sperm count, but also sperm motility and morphology.
"In my view, there is absolutely no doubt that male reproductive health has changed for the worse over the last 70+ years and it is a real concern in terms of the negative impact on a couple's fertility potential," Professor Richard Sharpe told Euronews. from the University of Edinburgh's Center for Reproductive Health.
Some of the main causes in reducing sperm count are: exposure to chemicals, obesity, stress, sedentary life, alcohol and drug use
What can men do to protect fertility? "It may sound boring and weird, but eating a balanced diet with lots of fresh fruit and vegetables and low amounts of processed foods is the best thing people can do," Sharpe said.
It emphasizes the importance of physical activity, maintaining a healthy weight and not smoking. Smoking is strongly associated with infertility.