If your man is experiencing problems with his fertility, he is not alone. Sperm counts have dropped significantly in the last 50 years in developed countries worldwide and in Europe, at least one in five 18- to 25-year-old men have semen quality in subfertile range, according to a report on male fertility from the European Science Foundation, released November 28, 2010.
Using data gathered from previous research, the report also notes that testosterone levels in men appear to be in decline, as evidenced by increasing rates of testicular cancer and undescended testes, a developmental abnormality noted in some newborn boys.
What does this mean for couples having trouble conceiving? Though more than 10 percent of couples worldwide are infertile, "the important impact of men's reproductive health on a couple's fertility is often overlooked," says Professor Niels Skakkebæk from the University of Copenhagen, who co-authored the report. "Women postponing motherhood have reduced fertility, and we now see that poor may be making it even harder to conceive. While poor sperm may be part of the reason more couples are using IVF it may also be making those therapies less successful."
Lifestyle factors such as obesity and smoking can affect sperm counts, according to scientists. But for many men, fertility problems may be in place before they are even born. As studies have found, when women smoke heavily in pregnancy, their sons are more likely to experience low sperm counts when they grow up. Other reasons for low sperm counts and declining testosterone levels may be due to environmental contaminants, though findings on this connection are still unclear.