Sexual Conditions Health Center

Aside from colds and the flu, sexually transmitted infections (STIs) are some of the most widespread infections both in the United States and the world. STIs affect both men and women, and almost half of all STIs occur in people younger than 25 years old. Exposure to an STI can occur any time you have sexual contact with anyone that involves the genitals, the mouth (oral), or the rectum (anal). Exposure is more likely if you have more than one sex partner or do not use condoms. Some STIs can be passed by nonsexual contact, such as by sharing needles or during the delivery of a baby or during breast-feeding. Sexually transmitted infections (STIs) are also called sexually transmitted diseases (STDs).

STIs are a worldwide public health concern because there is more opportunity for STIs to be spread as more people travel and engage in sexual activities. Some STIs have been linked to an increased risk of certain cancers and infection with human immunodeficiency virus (HIV). Pregnant women can spread STIs to their babies. Many people may not have symptoms of an STI but are still able to spread an infection. STI testing can help find problems early on so that treatment can begin if needed. It is important to practice safe sex with all partners, especially if you or they have high-risk sexual behaviors. See the Prevention section of this topic.

If you think you may have symptoms of an STI:

• Do not have sexual contact or activity while waiting for your appointment. This will prevent the spread of the infection.
• Women should not douche. Douching changes the normal balance of bacteria in the vagina. Douching may flush an infection up into your uterus or fallopian tubes and cause pelvic inflammatory disease (PID).

Common sexually transmitted infections

There are at least 20 different STIs. They can be caused by viruses, bacteria, and protozoa. Some of the most common STIs in the U.S. are:

• Chlamydia.
• Genital herpes.
• Genital warts or human papillomavirus (HPV). Certain high-risk types of HPV can cause cervical cancer in women.
• Gonorrhea.
• Hepatitis B.
• Syphilis.
• Trichomoniasis.
• Human immunodeficiency virus (HIV), which causes AIDS. Having other STIs, such as genital herpes, can increase your risk of HIV.
• Other infections that may be sexually transmitted. These include hepatitis A, cytomegalovirus, molluscum contagiosum, Mycoplasma genitalium, hepatitis C, and possibly bacterial vaginosis.
• Scabies and pubic lice, which can be spread by sexual contact.

Bacterial STIs can be treated and cured, but STIs caused by viruses usually cannot be cured. You can get a bacterial STI over and over again, even if it is one that you were treated for and cured of in the past.

Sexually active teens and young adults