Cause: the bacteria Chlamydia trachomatis

Symptoms: A woman might notice an unusual vaginal discharge, have pelvic pain or have bleeding even though she's not due for her period. She might have a menstrual period that is unusually long, heavy or uncomfortable. In severe cases she might have general abdominal pain. Unfortunately a large number of women have no symptoms or such mild symptoms that they are easy to ignore. The amount of symptoms does not always correlate with the extent of the damage. Mild symptoms can still cause difficulty in getting pregnant in the future.

Approximately half of men infected with chlamydia have no symptoms. If they do show signs of the disease it may be a slight discharge from the penis or a slight tingling or burning at the tip of the penis when urinating. Pain in the testicle area can occur in complicated infections. If the testicle area is involved, the future fertility of the man might be in danger.

Complications: Chronic pain and infertility can occur in women. Infertility can occur in men.

Treatment: Antibiotics are very effective in curing this infection.

Prevention: Condoms provide a high level of protection.