Sexually Transmitted Infection (STI) Tests

STIs (sexually transmitted infections) or sexually transmitted diseases (STDs) are infections that are passed from one person to another through sexual contact. STIs are usually spread during vaginal, oral, or anal sex. But sometimes, they can spread through other sexual contact involving the penis, vagina, mouth, or anus.

This is because some STIs, like herpes and HPV (human papillomavirus), are spread by skin-to-skin contact. Other ways that some STIs may be spread include: Through close personal contact, such as kissing; During pregnancy to the fetus or during childbirth; During breastfeeding; Through blood transfusions; By sharing needles; Certain bacteria, viruses, and parasites cause STIs. Millions of Americans get an STI every year, and many of those infections are in teens and young adults.

Common STIs include chlamydia, gonorrhea, genital herpes, HIV, and HPV infection. Left untreated, certain STIs can cause long-term health problems such as blindness, brain damage, infertility, birth defects, and even death. Fortunately, all STIs can be treated, and some can be cured.

However, that doesn't prevent you from getting infected again if you don't take steps to prevent infection. STI testing can help you get diagnosed and treated so you may avoid serious complications.

Why this test is done

STIs don't always cause symptoms, so catching or spreading an infection is possible even if you or your partner seem healthy. That's why STI screening tests are important. They look for diseases before you have symptoms.

Anyone who is sexually active could get an STI. So talk to your health care provider about your risk for HIV and other STIs and whether you need to be tested. If you are sexually active, you might consider getting a yearly test for HIV.

Other STI testing is mostly recommended for people who are at higher risk for certain STIs:

• Sexually active women under the age of 25. Experts recommend that women in this age group get a chlamydia test and a gonorrhea test every year. Sexually active women 25 years and older should be tested if they have new or multiple sex partners or have a partner who has been diagnosed with an STI.
• Women 21 to 30 years old. Women in this age group should get a Pap smear to check for cell changes in the cervix that could become cancer if not treated. These can be caused by HPV (human papillomavirus).
• Women 30 years and older. Women in this age group should talk to their provider about whether to get a Pap smear, HPV test, or both.
• If you are pregnant, you will usually be tested for HIV, hepatitis B, chlamydia, and syphilis. If you are pregnant and have certain risk factors, you may also be tested for gonorrhea and hepatitis C.
• Sexually active men and women who have unprotected sex (sex without a condom) and have more than one sexual partner. They should be tested regularly for HIV and other STIs as recommended by their provider.
• Men who have sex with men. Compared with other groups, men who have sex with men and bisexual men have a higher risk of STIs. Men in this group should be tested at least once a year for syphilis, chlamydia, gonorrhea, and HIV. Men with multiple partners may benefit from more frequent testing.
• People with HIV. If you have HIV, you are at higher risk of getting another STI. People in this group should be tested for syphilis, gonorrhea, and herpes. A chlamydia test is also usually recommended.
• People who use injectable drugs. Sharing needles puts you at risk for HIV. Regular HIV testing is recommended for this group.

Some STIs do not cause symptoms or may only cause mild symptoms. So it is possible to have an infection and not know it. Symptoms vary depending on the type of STI, but you may need testing if you have one or more of the following symptoms:

• Painful or frequent urination (peeing)
• Pain during sex
• Unusual odor in vaginal discharge
• Vaginal itching
• Discharge and/or itching from the penis
• Sores or bumps in the genital or rectal area
• Blisters or sores in or around the mouth
• Anal itching, soreness, or bleeding

Even without symptoms, STIs can still be harmful and may be passed on to your partner during sex.

How to prepare

You don't need any special preparations for a blood test. Women may need to avoid douches and vaginal creams for 24 hours before a urine or swab test.

You may need to empty your bladder before a lumbar puncture.

Your provider will let you know if you need other preparations.

Sample type

Blood Urine Swab CSF

Other names for this test

STD screening, STI (sexually transmitted infection) tests, STI screening, STD testing