Australian experts have responded to a new study which found men’s sperm count has dropped by nearly 60 per cent in the last four decades.
In the meta-analysis of 185 studies, the researchers from the Hebrew University of Jerusalem and the Icahn School of Medicine found a 52.4 percent decrease in sperm concentration and a 59.3 percent decrease in total sperm count.
The research, published in Human Reproduction Update, is an “urgent wake-up call” to explore the causes said the study’s lead author.
“If we will not change the ways that we are living and the environment and the chemicals that we are exposed to, I am very worried about what will happen in the future. Eventually we may have a problem, and with reproduction in general, and it may be the extinction of the human species,” lead researcher Dr Hagai Levine told the BBC., although other experts said the research and Levine’s claims should be treated with caution.
Given the falling sperm counts were specific to men from North America, Europe, Australia and New Zealand, it suggests lifestyle factors are to blame; factors that can be reversed.
“The most likely cause of this halving of sperm count is obesity,” said Kelton Tremellen a professor of Reproductive Medicine at Flinders University. “Poor diet and lack of exercise, both endemic in the western world, has resulted in two-thirds of men being overweight or obese, and obesity is known to be a significant risk factor for both low testosterone levels and sperm count.”
Tremellen reiterated that the research should be a “wake-up call” for men to look at their lifestyles.
“By maintaining a healthy weight, plus eating plenty of good foods like fish, nuts, fresh fruit and vegetables, while avoiding high fat and sugar foods, will help maintain both a healthy sperm count and good overall health,” he said.
Professor Rob McLachlan, the director of Andrology Australia said that while the research initially appears “alarming” it is nothing new.
“While not providing new primary data, it provides a meta-analysis of the hundreds of papers that have examined the semen quality over many years,” he said.
McLachlan agreed that lifestyle factors and obesity need to be addressed “and generally the role of environmental toxicants for which there is certainly evidence in more select populations”.
Up to 7 per cent of western populations are now conceived using assisted reproductive technology (ART), he explained.
“Male factor infertility accounts solely or in part for half of ART treatment,” McLachlan said.
According to Andrology Australia, a man’s fertility relies on the quantity and quality of his sperm. “If the number of sperm a man ejaculates is low or if the sperm are of a poor quality, it will be difficult, and sometimes impossible, for him to cause a pregnancy,” the men’s health site explained.
It is estimated that low sperm counts affect about one in 20 Australian men, while one in 100 have no sperm in their ejaculate.
“We are not in crisis yet but this study serves as a warning that we should investigate the role our diet and environment play on sperm production,” said Dr Shaun Roman, the head of biology in the School of Environmental and Life Sciences at the University of Newcastle.