Infections from three sexually transmitted diseases have hit another record high.
Chlamydia was the most common. More than 1.5 million cases were reported in the U.S. last year, up 6 percent from the year before.
Nearly 400,000 gonorrhea cases were reported, up 13 percent. And there were about 24,000 cases of the most contagious forms of syphilis, up 19 percent.
