Chlamydia is a very dangerous STD as it ususally has no symptoms; 75% of infected women and 25% of infected men have no symptoms at all.

Type: Bacterial

Modes of Transmission: Vaginal and anal sex.

Symptoms: Up to 75% of cases in women and 25% of cases in men are asymptomatic. Symptoms may include abnormal genital discharge, and burning during urination in both men and women. Women may also experience lower abdominal pain or pain during intercourse, and men may experience swelling or pain in the testicles.

Treatment: Infection can be cured with antibiotics. However, it cannot undo the damage done prior to treatment.

Possible Consequences for the Infected Person: If untreated in women, up to 30% will experience pelvic inflammatory disease (PID) which in turn often leads to ectopic pregnancy, infertility, and chronic pelvic pain. In men, if untreated, chlamydia can cause epididymitis, an inflammation of a testicle (where sperm are stored), which may result in sterility. Infected individuals are at greater risk of contracting HIV if exposed to the virus. See end of this document for information on PID and ectopic pregnancy.

Possible Consequences for the Fetus and Newborn: Premature birth; infant pneumonia and neonatal eye infections may result from transmission of the disease during delivery.

Prevention: Abstaining from vaginal and anal sex with an infected person is the only 100% effective means of prevention. Latex condoms can reduce but not eliminate the risk of contracting the disease.

CDC estimates that 3-5 million cases of genital chlamydial infections occur among U.S. adults each year. The economic burden of sexually transmitted chlamydial infections and related sequelae including PID, ectopic pregnancies, and tubal infertility exceeds $3.5 billion annually. Infections range from female lower genital tract infection and PID in women to urethritis, proctitis, and epididymitis in men, and to neonatal inclusion conjunctivitis and pneumonitis syndromes.