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Prenatal Group B Strep (GBS) Screening

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Also known as: Group B Beta-hemolytic Streptococcus; Group B Streptococcus; Group B Strep; GBS; Strep Group B; Streptococcus agalactiae; Beta-hemolytic Strep Culture
Formal name: Prenatal Group B Streptococcus Screening

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At a Glance

Why Get Tested?

To screen a pregnant woman for the presence of group B streptococcus (GBS) in her vagina or rectum to determine the risk that she will pass the bacteria on to her newborn during labor and delivery, possibly resulting in a serious infection in her newborn called early-onset GBS

When to Get Tested?

When a woman is between 35 and 37 weeks of pregnancy or has preterm labor or preterm premature rupture of membranes

Sample Required?

A swab obtained from the vagina and rectum of a pregnant woman; a urine sample collected anytime during pregnancy may be used to detect significant numbers of GBS.

Test Preparation Needed?

None