(RxWiki News) According to a new report by the European Science Foundation (ESF), reduced male fertility may be making it harder for couples to conceive.
With more than 10 percent of couples worldwide being infertile, less fertile males could be part of the reason for lower birth rates in many countries.
Researchers often focus on the role of women in infertility, specifically their increasing postponement of motherhood. However, the ESF report shows that men's reproductive health plays a crucial role. Both testosterone levels and quality of semen are declining in much of the world. Testicular cancer is increasingly common in industrialized countries, as are developmental abnormalities such as undescended testes.
According to Professor Niels Skakkebaek from the University of Copenhagen, co-author of the report, "That this decrease in male reproductive health has occurred in just a few decades suggests it's caused by environmental and lifestyle factors rather than genetics. So it is preventable if we correctly identify the causes."
Some lifestyle factors such as obesity and smoking can affect a man's sperm count but only minimally. Testosterone, on the other hand, naturally drops as men grow older. Lower levels of testosterone in men can lead to cardiovascular and metabolic health problems. Both low sperm counts and low testosterone are associated with an increased risk of early death for men.
