CANNABIS may slow down sperm, says Herbert Schuel of the State University of New York at Buffalo. This could explain reports of low fertility among men who smoke a lot of marijuana.
Schuel's team treated sperm in a test tube with a synthetic anandamidea chemical very similar to the active ingredient of cannabis. Low levels sent sperm swimming into overdrive, but higher levels slowed their motion to a lazy crawl. The chemical also inhibited the ability of the sperm to bind to the egg and penetrate it. "It really stops them cold," Schuel says.
Natural anandamides are present in semen, and are also secreted by the oviduct and egg follicles, Schuel's team has found. The researchers presented their results at a meeting of the American Society for Cell Biology in San Francisco.
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