Motor vehicle crashes cause one-third of teenage deaths and many serious injuries. Teen drivers ages 16 to 19 are four times more likely than older drivers to crash. Death and injuries could be reduced with a change in behaviors that include improved visual and attention skills while driving, more seat belt use, appropriate speed control, and not combining drinking or texting with driving. Sexually transmitted infections (STIs) and unplanned pregnancies are particularly common among adolescents. The U.S. adolescent birthrate is by far the highest among industrialized nations. These problems can be decreased by less sexual activity and better protection.