Count is not the only factor that affects fertility but also other aspects such as sperm rate
PARIS – The Count of semen of men worldwide are declining at an accelerating rate after declining by 50% over the past 40 years, reveals a new study published this month in the journal Human Reproduction Update🇧🇷
The work, led by Israeli epidemiologist Hagai Levine, updates a 2017 survey that was being expanded to include only North America, Europe, Australia and New Zealand. The new study includes data from more than 57,000 men gathered from 223 studies in 53 countries, making it the largest meta-analysis ever conducted on the topic.
As new countries were added, it confirmed the 2017 conclusion that the semen it has halved in the last four decades.
Between 1973 and 2018, sperm concentration in men known to be infertile decreased by more than 51 percent, from 101.2 million to 49 million sperm per millimeter of semen, according to the new study.
“Furthermore, the data suggest that this worldwide decline continues into the 21st century at an accelerating rate,” said the international researchers in the study published in the journal Human Reproduction Update🇧🇷 Sperm count is decreasing at a rate of about 1.1% per year, survey finds. More action and research is urgently needed “to prevent further disruption to male reproductive health,” she added.
“We Really Don’t Know Why”
Sperm count is not the only factor that affects fertility. The speed of sperm movement, which was not measured in the study, also plays a crucial role.
And the lowest sperm concentration, 49 million, is still well above the range considered “normal” by the World Health Organization (WHO) – between 15 million and 200 million sperm cells per millilitre.
Sarah Martins da Silva, a reproductive medicine specialist at the University of Dundee in Scotland, who was not involved in the study, said the study showed that the rate of decline in semen it’s doubled since 2000. “And we really don’t know why,” he added.
“Exposure to pollution, plastics, smoking, drugs and prescription medications, as well as lifestyle factors such as obesity and poor diet, have all been suggested as contributing factors, although the effects are little known and poorly defined”. Other experts said the new study didn’t resolve their skepticism about the 2017 research.
“I remain concerned about the quality of the data in the papers that have been published, particularly in the distant past” on which the analysis is based, said Allan Pacey of the University of Sheffield in the UK.
While lauding the “very elegant meta-analysis,” Pacey said he thought we “just got better” at the difficult task of counting sperm, which could explain the drop in rates. But Sarah, of the University of Dundee, dismissed criticism of the study findings, saying ‘the numbers and the consistent results are hard to ignore,’ she added. /AFP
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Source: Terra
Ben Stock is a lifestyle journalist and author at Gossipify. He writes about topics such as health, wellness, travel, food and home decor. He provides practical advice and inspiration to improve well-being, keeps readers up to date with latest lifestyle news and trends, known for his engaging writing style, in-depth analysis and unique perspectives.
