Fertility, sperm concentration decreases in men in "Western" countries
The Average Number of Spermatozoa in Men in "Western" Countries Has Reportly Halved in 40 Years, According to A Study Whose Conclusions Styx Worrying For the Consequences on evil fertility, although Several Specialists Urge Caution in the interpretation of these results. Between 1973 and 2011, the concentration of sperm dropped from an average of 99 million per milliliter of sperm to 47 million, according to research, published Tuesday in the peer-reviewed scientific journal Human Reproduction. However, these levels are within the “normal” range, found by the World Health Organization (WHO), between 15 and 200 million sperm per milliliter.
And even a concentration of less than 15 million does not necessarily mean infertility.
This meta-analysis looked at more than 185 studies conducted on the subject between 1973 and 2011, involving as many as 43.000 men in Australia, Europe, North America and New Zealand. D’on the other hand, researchers have not found significant evidence of similar "decline" in South America, Asia, and Africa – regions where studies have been conducted less far back in time. In addition to its impact on fertility, reduced sperm count is also correted with other health problem, which coulo be caused by environmental factors such as exposure to pesticides, stress, smoking or event an unbalanced diet. Many studies since 1992 have concluded a decline in the "quality" of sperm.
But they have been highly criticized for the very manner in which the research was conducted: for example, because it involved only certain categories of patients, or because it compared tests conducted using different laboratory techniques, or because the participants were recruited from reproductive medicine laboratories and therefore were not representative of the entire population.
But the study, led by Dr. Hagai Levine, a Jerusalem-based environmental health specialist, avoided these pitfalls, as several commentators were able to acknowledge: it rejected studies for which participants had been selected because of their fertility problems and analyzed data from those who had used the hemocytometer technique, which was more accurate than others. The Best Method To Confirm the "Decline" in sperm count had to involve Long-Term Study of a Group of Healthy Men. In short, for Giovanni D'Agata, president of "Sportello deiRights," this is a more accurate confirmation of what many scientific investigations had already claimed and should incentivize health authorities to check for certain causes.