Count carefully!

Scientists have explained a 59% reduction in the number of sperm in Western men

Georgy Golovanov, Hi-tech+

A number of recent studies have found that in modern men, especially from Western countries, the number of spermatozoa has halved compared to the mid-70s of the last century, and this is an alarming sign. Some even started talking about the extinction of Western civilization. Scientists from the Harvard GenderSci laboratory conducted an analysis of spermograms used, among other things, in the sensational meta-analysis of 2017, and came to the conclusion that there is no reason to panic.

Article by Boulicault et al. The future of sperm: a biovariability framework for understanding global sperm count trends is published in the journal Human Fertility – VM.

A major 2017 study found an average 59 percent reduction in the number of sperm in Western men between 1973 and 2011. The analysis used data from 124,000 people living in Europe and the USA. The rate of reduction is about 2% per year.

Harvard scientists have proposed another explanation for the trend of decreasing the number of sperm in the ejaculate of men. In their opinion, this indicator can vary significantly within the normal range, and that a larger number of spermatozoa is not necessarily an indicator of good health and high fertility.

The authors of the article in the journal Human Fertility claim that their approach to biological variability better corresponds to the results of important studies of factors affecting the reproductive health of men, writes Harvard Gazette. They point to a number of statements that are questionable from the point of view of science and ethics, on which the assumption of a serious decline in the fertility of Western men is based:

• The statement about the sharp drop in the number of spermatozoa is based on the assumption of the optimum, which was allegedly achieved in the 1970s among the population of English-speaking countries.
• A decrease in the number of spermatozoa does not mean a decrease in fertility. The claim that male fertility depends on the number of spermatozoa is not supported by evidence.
• The claim that the decrease in the number of sperm is caused by the effect of chemicals on the endocrine system is not confirmed by geographical and historical patterns of population distribution.
• The use of the designations "Western" and "other" used in a large 2017 study is unjustified from a scientific point of view. Static generalizations obscure the differences between residents of cities and villages, as well as the fact that there are very few spermograms among men living in countries called "others".

"Researchers should carefully weigh the options for hypotheses and choose the language and style in which they present their ideas," the article concludes. They complain that the meta-analysis of 2017 was used for their own purposes by supporters of right-wing views and the concept of white supremacy to accuse immigrants and feminists of jeopardizing Western civilization.

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