What are sexual transmitted infections (STIs)?
STIs are infections that are passed from person to person through sexual contact, including oral sex.
STIs may be caused by different types of germs, including chlamydia Chlamydia Chlamydia are bacteria that can cause several kinds of infection. One common chlamydia infection is a sexually transmitted infection (STI). An STI is an infection that is spread from person... read more , gonorrhea Gonorrhea Gonorrhea is a sexually transmitted infection (STI). An STI is an infection that is spread from person to person by sexual contact. Gonorrhea infects your genitals and, in women, your fallopian... read more , HIV Human Immunodeficiency Virus (HIV) Infection and AIDS The human immunodeficiency virus (HIV) is a type of virus called a retrovirus. It causes AIDS (acquired immunodeficiency syndrome), which is life-threatening. HIV is called an immunodeficiency... read more , and syphilis Syphilis Syphilis is a sexually transmitted infection (STI). An STI is an infection that is spread from person to person by sexual contact. Syphilis spreads easily through anal, oral, or vaginal sex... read more
Some STIs can be spread through kissing or close body contact, not just intercourse
Some STIs can cause very serious health problems throughout your whole body
Using condoms can help prevent STIs
Pathway From the Vagina to the Ovaries
In women, some organisms can enter the vagina and infect other reproductive organs. From the vagina, these organisms can enter the cervix and uterus and may reach the fallopian tubes and sometimes the ovaries.  |
Pathway From the Penis to the Epididymis
Occasionally in men, organisms spread up the urethra and travel through the tube that carries sperm from the testis (vas deferens) to infect the epididymis at the top of a testis.  |
What causes STIs?
STIs are caused by tiny viruses, bacteria, and parasites, depending on the disease. People who have sex with an infected partner can get an STI. The sex can be vaginal, oral, or anal. However, some STIs also can be spread in other ways, including:
Kissing or close body contact
From mother to child before or during birth
Breastfeeding
What are the symptoms of STIs?
Some STIs do not cause symptoms. If you do have symptoms of an STI, you may have:
Sores on your genitals or mouth
Discharge from the sores or your genitals
Pain or itching
Pain when urinating (peeing)
If you don't get treated quickly, some STIs can cause more serious problems:
Heart and brain infections
Cancer
Infertility (when you can't get pregnant)
How can doctors tell if I have an STI?
Doctors may do tests on your blood, urine, or on a sample from your penis, vagina, throat, or rectum.
If you have one STI, doctors also do tests for other STIs—people who have one STI have a relatively high chance of having another one.
How can I prevent STIs?
Practice safe sex
Get vaccines (shots)
There are vaccines to prevent some STIs:
How do doctors treat STIs?
Most STIs can be treated with medicines. Some viral STIs can't be cured, so you have them for life.
