More than 1 million cases of chlamydia were reported in the United States last year -- the most ever reported for a sexually transmitted disease, federal health officials said

More bad news: Gonorrhea rates are jumping again after hitting a record low, and an increasing number of cases are caused by a "superbug" version resistant to common antibiotics

Syphilis is rising, too. The rate of congenital syphilis -- which can deform or kill babies -- rose for the first time in 15 years.

The CDC releases a report each year on chlamydia, gonorrhea and syphilis, three diseases caused by sexually transmitted bacteria.

Chlamydia is the most common. Nearly 1,031,000 cases were reported last year, up from 976,000 the year before.