Declining sperm quality is a worldwide issue, and evening screen time might be making the problem worse. A new study appears to link smartphone and tablet use at night with poor sperm quality

This is the first study to show a clear correlation between exposure to short-wavelength light from digital media such as tablets and smartphones, in the evening and after bedtime. The study also showed that men who slept for longer also had better sperm motility. 

The study used self-reported screen time data and measured sperm quality in several ways. Sperm in men who reported more gadget use at bedtime had lower motility (ability to swim), which can negatively impact conception. 

The principal investigator Amit Greene said “Smartphone and tablet use in the evening and after bedtime was correlated with a decline in sperm quality. Furthermore, smartphone use in the evening, tablet use after bedtime, and television use in the evening were all correlated with the decline of sperm concentration.”

Dr. Greene is the head of research and development at the Sleep and Fatigue Institute at the Assuta Medical Center in Tel-Aviv, Israel.

Men who want to optimise their sperm quality can limit their use of tablets, smartphones and even televisions in the evening, and before bedtime. A healthy sleep schedule may also help to improve sperm quality and motility.