Actually it could end up being good news, because fewer people means less damage to the environment we depend on for life.
https://news.yahoo.com/male-fertility-crash-accelerating-worldwide-222355509.html
The Hill
Saul Elbein
Tue, November 15, 2022 at 5:23 PM
The world is experiencing a quiet yet accelerating collapse in male fertility, according to a paper published Tuesday in the journal Human Reproduction Update.
The study found sperm counts fell by more than 51 percent between 1973 and 2018. And while sperm counts have been dropping for decades, the decline rate appears to be speeding up.
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The rate of decline since 2000 has been striking, the study found, with an observed 2.64 percent fall each year in the number of sperm per milliliter of semen — more than twice as large of a decline as that observed since 1978, according to The Guardian.
While reasons for the decline are unclear, one major factor could be endocrine-disrupting chemicals found in thousands of everyday items, co-author Shanna Swan of the Icahn School of Medicine told the Financial Times.
These compounds — found in everything from personal care products to food packaging — have particularly dire impacts on reproductive function, Swan noted. She specifically called out phthalates and bisphenols, compounds used as linings in products such as water bottles and takeout containers.
Levine and Swan’s joint study builds on existing findings that have linked environmental chemicals to persistent rates of decline in sperm counts.
A 2021 Danish study listed chemicals found in or derived from fossil fuels as possible culprits, as The Hill reported.
Potentially harmful chemicals from such sources “have been found in samples of blood, urine, semen, placenta and breast milk of all humans investigated,” the study found.
“It is well established that these chemicals have become part of our tissues and fluids,” the authors added. “We know that they can be a threat to wildlife. Unfortunately, too little has been done to uncover their role in humans.”
Plastic derivatives such as bisphenol A (BPA) — commonly added to food and beverage packaging — have also been linked to declining male fertility as well as birth defects.
Many potentially toxic chemicals “reach us via food,” Andreas Kortenkamp, a professor at Brunel University London, said in June.
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Humans could face reproductive crisis as sperm count declines, study finds
Nicola Davis Science correspondent
@NicolaKSDavis
Tue 15 Nov 2022 05.00 EST
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Previous studies have suggested that fertility is compromised if sperm concentration falls below about 40m per ml. While the latest estimate is above this threshold, Levine noted that this is a mean figure, suggesting the percentage of men below this threshold will have increased.
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Tina Kold Jensen of the University of Southern Denmark said the new study recapitulated a concerning trend. “You keep on finding the same trend, no matter how many studies you include – that is a bit scary to me,” she said.
Prof Richard Sharpe, an expert in male reproductive health at the University of Edinburgh, said the new data showed that the trend appeared to be a worldwide phenomenon.
Sharpe said the decline could mean it takes longer for couples to conceive and, for many, time is not on their side as they are delaying trying to conceive until the woman is in her 30s or 40s, when her fertility is already reduced.
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