This is one of the most common STIs. It is caused by a bacterium that exists in vaginal secretions and semen ("cum"). It can be spread by vaginal, oral, or anal sex without a condom or latex/polyurethane barrier. Pregnant women can pass it on to their babies during delivery. Symptoms may include vaginal discharge and burning during urination, but most women do not have any symptoms. Chlamydia can be successfully treated with antibiotics. If left untreated, it can spread to a woman's upper, internal reproductive organs (ovaries and fallopian tubes) and cause pelvic inflammatory disease (PID). PID can lead to infertility, meaning that it may be difficult or impossible to become pregnant.
The CDC recommends yearly chlamydia screening for all sexually active women under the age of 25, as well as for older women with risk factors, such as new or multiple sex partners. Unfortunately, recent reports show that less than half of sexually active women under 25 are screened for chlamydia, in part because of a lack of awareness among health care providers. If you are not offered a chlamydia test, you may want to request one from your health care provider.
Genital warts are caused by viruses. HPV (Human Papillomavirus) is the name of a large group of viruses. Certain types of HPV cause warts on the hands or feet. Other types cause infections in the genital area that can lead to genital warts, cervical cancer, or cancer of the vulva, vagina, anus, or penis. Genital HPV is spread easily through skin-to-skin contact during vaginal, oral, or anal sex. Condoms do not entirely prevent transmission. People living with HIV are more likely to be infected with HPV than HIV-negative people. People living with HIV and HPV are also more likely to develop genital warts, as well as cervical or anal cancer.
It is important to find HPV early and get treatment to prevent health problems. Regular cervical screening tests are a good way to check for HPV. There are also three effective HPV vaccines. Since the introduction of the HPV vaccines several years ago, the number of 14- to 19-year old girls infected with HPV in the US has dropped by more than half. It is important for young people to get vaccinated before they have sex (before they have been exposed to HPV), since people who are already infected with HPV may not be protected by the vaccines. For more information, see our fact sheet on HPV.
Often called "the clap," this STI is transmitted by a bacterium in vaginal secretions and semen. It can be spread through vaginal, anal, or oral sex without a condom or latex/polyurethane barrier. Symptoms may include a yellowish or greenish vaginal discharge and a burning feeling when urinating. Gonorrhea can also affect the anus and the throat. Many women have no symptoms. Gonorrhea can be treated with antibiotics. If left untreated, it can cause PID and infertility. All sexually active women should be screened for gonorrhea.