People who have common sexually transmitted diseases may not have any apparent symptoms right away, warns Mayo Clinic. Symptoms that do develop for chlamydia include lower abdominal pain, painful urination, bleeding between periods, discharge from the penis or vagina and testicular pain in men. Gonorrhea, a common sexually transmitted disease, causes pain or burning sensations when urinating, painful bowel movements, anal itching, and thick, bloody or cloudy discharge from the vagina or penis.
Symptoms of trichomoniasis, a sexually transmitted disease caused by a parasite, produces symptoms such as a strong vaginal odor; itching or irritation inside the penis or vagina; painful urination; clear, greenish, yellowish or white vaginal discharge; and pain during sexual intercourse, according to Mayo Clinic.
The human immunodeficiency virus or HIV causes infected patients to develop flu-like symptoms, as the disease interferes with the immune system's ability to fight off fungi, bacteria and viruses, explains Mayo Clinic. HIV can lead to life-threatening conditions such as AIDS and causes symptoms such as fatigue, swollen lymph glands, a sore throat, fever, headache and a rash. A late-stage HIV infection can cause chronic diarrhea, shaking chills, soaking night sweats, unexplained fatigue and fevers, and persistent headaches accompanied by unexplained infections.