Global sperm counts in decline

Cigarette smokers were also shown to have higher levels of circulating estradiol and decreased levels of LH, FSH, and prolactin compared to non-smokers, all of these negatively impact spermatogenesis Meanwhile, total sperm count among the same group plunged 1. What's the perfect gift for someone who's constantly moving and traveling? It also explains the major possible causes of the declining trend. Without a clear set of risk factors for declining sperm count, Levine advised men to maintain a healthy lifestyle devoid of smoking, junk food, or sedentary behavior. The researchers noted, however, that far fewer studies have been conducted in these regions.

The study of sperm has always been murky. The Dutchman was the first person to observe human sperm cells, though he insisted that the sperm alone made an embryo that was merely nourished by the female egg and ovaries. Stress is also a risk factor, as is alcohol use, which is on an upswing in the U. According to the American Society for Reproductive Medicine, the male partner is either the sole or contributing cause in about 40 percent of cases of infertility. The downward trend found in the large meta-analysis of global sperm counts Credit:

Infertility can cause rifts in otherwise healthy relationships. Therefore, looking ahead, I can only conclude that couple infertility is set to increase. That dovetails with other research showing that as men age, their sperm suffers increasing numbers of mutations, which in turn can make it slightly more likely that their children will be born with disorders like autism and schizophrenia. Studies were included in the analysis if they looked at either men who were unaware of their fertility for example, men who had never tried to conceive or men who were deemed fertile for instance, men known to have conceived a pregnancy. Male Infertility, Medicine, and Identity. Not only that, the decline doesn't seem to be leveling off, so the trend is likely to continue. Sperm counts for men in North America, Europe, Australia and New Zealand have declined by more than 50 per cent in the last four decades, a large research review has found.

Similarly, hormonal imbalance was also found by Ozoemena et al. When it comes to contraception, what was old is new again. By excluding studies before , they cut out some of the less reliable older measurements, and they discarded any studies of men with known fertility complications or who were smokers, since smoking lowers sperm count. Open in a separate window. Although there have reports of declining sperm counts before, they were easy to ignore.