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Sexually Transmitted Infections (STIs)
What are sexually transmitted infections (STIs)?
STIs are generally passed from person to person through sexual contact. They may also be called sexually transmitted diseases (STDs). The bacteria, viruses or parasites that cause sexually transmitted diseases may pass from person to person in blood, semen, or vaginal and other bodily fluids.
How can you protect yourself from STIs?
The best way to prevent getting an STI is to not have sex, including oral, vaginal, or anal sex. But you can take steps to lower your risk for an STI if you decide to become sexually active or are currently sexually active. These include:
- Use a male latex condom the correct way every time you have sex.
- Prevent and control other STIs. Having one STI may increase your risk for others.
- Get the HPV vaccine before having sex for the first time or as soon as possible after becoming sexually active.
- Limit the number of sexual partners you have.
- Talk to your partners about your and their past STIs and HIV testing status, and whether either of you have any current STIs or genital symptoms.
- Have regular checkups for HIV and STIs.
- Learn the symptoms of STIs and seek medical help as soon as possible if any symptoms develop.
- Talk with your healthcare provider if you have had an STI or have multiple sexual partners. Ask your provider about preventing HIV infection by taking a preventive medicine called PREP (pre-exposure prophylaxis).
- If you have been exposed or diagnosed with an STI, ask your healthcare provider if your partner should be tested and treated as well and what precautions you should be taking.
What to do when diagnosed with an STI?
- Begin treatment right away. Take the full course of medicines and follow your healthcare provider's advice.
- Tell your recent sexual partners so that they can get tested and treated, too.
- Don't have sexual activity while getting treatment for an STI. Ask your healthcare provider when it is safe to have sex again.
What are some common types of STIs?
Common STIs include:
HIV is a virus that destroys the body's ability to fight infection. People who have HIV may not look or feel sick for a long time after infection. If you are not diagnosed early and treated, you are at high risk of developing many life-threatening diseases. The virus is passed on most often during sexual activity. It can also be passed on by sharing needles used to inject drugs. HIV can be passed to your baby during pregnancy, and labor and delivery, and through breastfeeding. If you know before becoming pregnant or early in your pregnancy that you are HIV-positive, you can get treatment that greatly lowers your chance of passing on the virus to your child.
Human papillomavirus (HPV)
HPV is one of the most common STIs. Some types of HPV can cause genital warts. These can happen on the inside or outside areas of the genitals. They may spread to the surrounding skin or to a sexual partner. Many other types of HPV cause no symptoms, so you may not know that you are infected. In most cases, the virus goes away and doesn't cause more health problems. But if the virus lasts, normal cells can change and become abnormal. Women with an HPV infection with high-risk types, such as HPV 16 and 18, have an increased risk of getting cervical cancer. Pap tests can find HPV infection, as well as abnormal cervical cells. An HPV vaccine protects against the types of HPV that cause most cervical cancers. It also protects against most genital warts in both men and women, and against anal cancer in men.
Chlamydia is the most commonly reported STI in the U.S. It can affect both men and women. It often causes no symptoms. If symptomatic, the infection may cause an abnormal genital discharge and burning with urination. In women, untreated chlamydia may lead to pelvic inflammatory disease (PID). Complications can occur in women including, tubal (ectopic) pregnancy and infertility. If you are pregnant and have chlamydia, the infection can be passed to your baby at birth. Chlamydia can be treated with antibiotics.
Gonorrhea may be present but cause no symptoms. Or it can cause a discharge from the vagina, penis, or rectum, painful or difficult urination or bowel movements, or a sore throat that doesn't go away. Complications can occur in women including, PID, tubal pregnancy, and infertility. Gonorrhea at the time of childbirth can spread to the baby. Gonorrhea can be treated with antibiotics.
Genital herpes infections are caused by the herpes simplex virus (HSV). HSV can be passed on from the mouth to the genitals, or from the genitals to the mouth, during oral sex. The virus can be passed on to sexual partners even if the person has no visible blisters. Symptoms may include painful blisters or open sores in the genital, buttock, or rectal area. The herpes sores usually disappear within a few days. The virus stays in the body for life, and the sores may return from time to time. There is no cure for HSV, but medicine can shorten an outbreak and ease symptoms.
The first symptom of syphilis is a painless open sore that usually shows up on the penis, in the vagina or mouth, or on the skin around the rectum or genitals. Untreated syphilis may go on to more advanced stages including a rash. Over time it can cause problems with the heart and central nervous system. If a pregnant woman has untreated syphilis, the disease can cause severe problems for the baby. Syphilis can be treated with antibiotics.
If you think you may have an SDI, contact your gynecologist or your obstetrician, if you are pregnant, as soon as possible. Many STIs can be successfully treated when diagnosed early.
Content sourced from the UCLA Health Krames StayWell Health library.