Group B streptococcus (GBS) is one of the many types of bacteria that live in the body and usually do not cause serious illness. It is found in the digestive, urinary, and reproductive tracts of men and women. In women, it can be found in the vagina and rectum. GBS is not a sexually transmitted infection. Also, although the names are similar, GBS is different from group A streptococcus, the bacteria that causes “strep throat.”
Most pregnant women who are colonized with GBS have no symptoms or health effects. In a small number of women, GBS can cause infections of the uterus and urinary tract. A woman who is colonized with GBS late in her pregnancy can pass it to her baby. We routinely test for Group B Strep in late pregnancy.