Conditions & Treatments

Sexually Transmitted Diseases (STDs)

Sexually transmitted diseases are infectious diseases transmitted through sexual contact.

Sexually Transmitted Diseases

What are sexually transmitted diseases (STDs)?

STDs are infectious diseases transmitted through sexual contact. It is estimated that 20 million new cases occur annually in the U.S. Half of the new infections occur in people between the ages of 15 and 24 years.

How can you protect yourself from STDs?

The best way to prevent contracting an STD is to abstain from any type of sexual activity, including oral, vaginal, and anal sex. However, if you decide to become sexually active, or are currently sexually active, there are several precautionary measures to help reduce your risk of developing a sexually transmitted disease. These include the following:

  • Have a mutually monogamous sexual relationship with an uninfected partner.

  • Use (consistently and correctly) a male latex or female polyurethane condom and topical microbicides.

  • Use sterile needles if injecting intravenous drugs.

  • Decrease susceptibility to HIV infections by preventing and controlling other STDs.

  • Delay having sexual relationships as long as possible. The younger a person is when he or she begins to have sex for the first time, the more likely he or she becomes to developing an STD.

  • Have regular checkups for HIV and STDs.

  • Learn the symptoms of STDs and seek medical help as soon as possible if any symptoms develop.

  • Avoid having sexual intercourse during menstruation.

  • Avoid anal intercourse, or use a male latex condom and topical microbicides.

  • Avoid douching.

What to do when diagnosed with an STD?

  • Begin treatment immediately, take the full course of medications, and follow your health care provider's advice.

  • Do not breastfeed a baby or use breast milk to feed a baby if you are HIV positive.

  • Notify all recent sexual partners and urge them to get medical checkups.

  • Avoid sexual activity while under treatment for an STD.

  • Have a follow-up test to be sure the STD has been successfully treated.

What are some common types of STDs?

According to the National Institute for Allergy and Infectious Diseases and Centers for Disease Control, common types of STDs include:

  • Human immunodeficiency virus (HIV). HIV is a virus that destroys the body's ability to fight off infection. People who have HIV may not look or feel sick for a long time after infection, but if not diagnosed early and treated, will eventually become very susceptible to many life-threatening diseases and to certain forms of cancer. Transmission of the virus most often occurs during sexual activity or by the sharing of needles used to inject intravenous drugs.

  • Human papillomavirus (HPV). HPV is a common sexually transmitted disease. Some types can cause genital warts called condylomas, which can occur on the inside or outside areas of the genitals and may spread to the surrounding skin or to a sexual partner. Many other types of HPV cause no symptoms, so the infection may go undetected. In most cases, the virus goes away and does not cause further health problems. However, if the virus persists, normal cells can change and become abnormal. Women with an HPV infection with high-risk types like HPV 16 and 18 have an increased risk of developing cervical cancer. Regular Pap tests can detect HPV infection, as well as abnormal cervical cells. Two types of HPV vaccines are available to protect girls and women against the types of HPV that cause most cervical cancers. One type also protects against most genital warts in girls and women and also protects boys and men against most genital warts and anal cancers. Although there is treatment for the genital warts (which sometimes go away on their own), the virus remains and warts can reappear. Certain types of HPV can also cause warts on other body parts such as the hands, called common warts; however, these do not generally cause health problems.

  • Chlamydial infections. Chlamydial infections, the most commonly reported STD, can affect both men and women. They may cause an abnormal genital discharge and burning with urination. In women, untreated chlamydial infection may lead to pelvic inflammatory disease (PID). Chlamydial infections can be treated with antibiotic therapy. Unfortunately, many people with chlamydial infection have few or no symptoms of infection. The most common and serious complications occur in women and include pelvic inflammatory disease, ectopic (tubal) pregnancy, and infertility. Chlamydia can also be carried in and affect the rectum as well as the genital areas.

  • Gonorrhea. Gonorrhea causes a discharge from the vagina or penis and painful or difficult urination. The most common and serious complications occur in women, and include pelvic inflammatory disease, ectopic (tubal) pregnancy, and infertility. Gonorrhea infections can be treated with antibiotic therapy. Gonorrhea can also be carried in and affect the rectum as well as the genital areas.

  • Genital herpes. Genital herpes infections are caused by the herpes simplex virus (HSV). Symptoms may include painful blisters or open sores in the genital area, which may be preceded by a tingling or burning sensation in the legs, buttocks, or genital region. The herpes sores usually disappear within a few weeks, but the virus remains in the body and the lesions may recur from time to time. There is no cure for HSV, but there are antiviral agents to take that can shorten an outbreak and reduce symptoms. HSV can be transmitted from the mouth (if a person has ever had cold sores, also caused by HSV) to the genitals during oral sex. The virus can be transmitted to sexual partners even if there are no visible blisters. This is called asymptomatic shedding. 

  • Syphilis. The initial symptom of syphilis is a painless open sore that usually appears on the penis, in the vagina, or on the skin around either sexual organ. Untreated syphilis may go on to more advanced stages, including a transient rash and, eventually, serious involvement of the heart and central nervous system. Syphilis infections can be treated with antibiotic therapy.

  • Other diseases that may be sexually transmitted include:

    • Bacterial vaginosis

    • Chancroid

    • Cytomegalovirus infections

    • Granuloma inguinale (donovanosis)

    • Lymphogranuloma venereum

    • Molluscum contagiosum

    • Pubic lice

    • Scabies

    • Trichomoniasis

    • Vaginal yeast infections

What are the facts about STDs and teens?

STDs affect men and women of all backgrounds and economic levels. However, nearly half of all STD cases occur in people younger than age 25 in the U.S.

STDs are on the rise, possibly due to more sexually active people who have multiple sex partners during their lives.

Many STDs initially cause no symptoms. In addition, many STD symptoms may be confused with those of other diseases not transmitted through sexual contact--especially in women. Even symptomless STDs can be contagious.

Women suffer more frequent and severe symptoms from STDs:

  • Some STDs can spread into the uterus (womb) and fallopian tubes and cause PID, which can lead to both infertility and ectopic (tubal) pregnancy.

  • STDs in women also may be associated with cervical cancer.

  • STDs can be passed from a mother to her baby before or during birth. Some infections of the newborn may be successfully treated, but others may cause a baby to be permanently disabled or even die.

When diagnosed early, many STDs can be successfully treated.

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