Men aren’t producing as many sperm as they were decades ago. It’s a trend observed around the globe. The pace of decline is accelerating. Those are the headline findings of a new analysis of sperm count studies published Tuesday in the journal Human Reproduction Update. It’s the largest report to examine the issue. In a news release, the researchers behind the analysis framed their findings as a “looming crisis” and a “canary in a coal mine” that could “threaten mankind’s survival.” Shanna Swan, an author of the new analysis, said in an interview that the new research should sound alarms...