What are sexually transmitted infections (STIs)?Sexually transmitted infections, or STIs, are infections passed from one person to another during sex. Any type of sex can cause an STI. It can be penis to vagina sex, or penis to anus sex, or oral sex (mouth to penis, mouth to vagina). Sometimes STIs can happen from just rubbing an infected penis or vagina against another person’s genitals. STIs can be passed from a pregnant woman to her baby before it is born, or during childbirth. STIs increase the risk of getting or giving HIV.
Unless they are treated early, STIs can cause:
- infertility in both men and women.
- babies born too early, too small, blind, sick, or dead.
- pregnancy in the tube (outside the womb).
- death from severe infection.
- lasting pain in the lower abdomen.
- cancer of the cervix.