“We should be amazed and worried by the finding,” said Prof. Hagai Levine of the Hebrew University of Jerusalem, who led the peer-reviewed study together with Prof. Shanna Swan at New York’s Icahn School of Medicine. “The trend of decline is very clear,” told The Times of Israel. “This is a remarkable finding and I feel responsible to deliver it to the world. The decline is both very real and appears to be accelerating.”
The previous study conducted in 2017 gained widespread attention after reporting that sperm counts in Australia, New Zealand, America, and Europe had decreased by over 50% between 1973 and 2011. This study adds 7 more years to the statistics and great geographical reach, covering 1973 to 2018 in over 53 countries, and suggests that it has dropped 62%.
The conclusion was reached by analyzing hundreds of peer-reviewed studies and adjusting the overall statistics to eliminate any potentially distorting data, such as not including men who had their sperm counts checked because of fertility problems.
Sperm count means the number of sperm present in an average ejaculation, according to the authors the sperm count per milliliter is down 52% which represents around 50 million. Although this is above the W.H.O’s cutoff point for a low sperm concentration of 15 million per milliliter, Levine cites other research indicating that fertility starts to decline when the concentration falls below 40 million per milliliter and said that with the current rate of decline that number is set to be global within 10 years.
“What is more, we’re looking at averages, and if men are today averaging 50 million sperm per milliliter, there are large numbers of men who today have under 40 million sperm per milliliter — in other words, fertility that is actually suboptimal,” says Levine.
“Our findings serve as a canary in a coal mine. We have a serious problem on our hands that, if not mitigated, could threaten humankind’s survival. We urgently call for global action to promote healthier environments for all species and reduce exposures and behaviors that threaten our reproductive health,” warns Levine.
Since 2000 there has been a steady decline in sperm counts of around 2.64% annually, this is more than double the decline seen dating back to 1978. Although this study does not investigate what is causing this decline, other researchers have linked the falling counts to the widespread epidemics of obesity and a sedentary lifestyle, as well as smoking, exposure to pesticides, exposure to certain chemicals such as endocrine disrupting chemicals, and other detrimental factors. The authors note that the declining sperm counts are a part of another issue, the wider decline in aspects of men’s health.
“The troubling declines in men’s sperm concentration and total sperm counts at over 1% each year as reported in our paper are consistent with adverse trends in other men’s health outcomes,” she said. “These include testicular cancer, hormonal disruption and genital birth defects, as well as declines in female reproductive health. This clearly cannot continue unchecked.”
