What should you know about a GBS blood test in pregnancy?

Group B Streptococcus is a bacterium that can live in the digestive or genital tract without causing illness. A blood result is interpreted in context and is not the same as a routine test for every pregnancy concern. The maternity team considers your symptoms, pregnancy history, test method, and whether there are signs of infection. A positive finding does not mean you are seriously ill, while a negative result does not remove the need to report new symptoms during labour or pregnancy.

Ask which sample is being tested, why it was requested, and when the result will be available. Follow the collection instructions and tell the team about antibiotics, allergies, previous GBS findings, or a history of an affected newborn. Keep the result with your maternity records and tell the labour ward when labour starts or your waters break. Do not start or stop antibiotics without advice; the team will explain whether treatment is needed and when.

Contact your maternity unit urgently for fever, feeling suddenly very unwell, reduced fetal movement, vaginal bleeding, regular contractions, or fluid leaking from the vagina. Tell them promptly about a known GBS result, especially when labour begins or the waters break, so they can assess you without relying on memory of the report.

What does this result mean for my pregnancy and birth plan? Was a blood test the intended GBS test? Do I need another sample, monitoring, or antibiotics, and what should I do if labour or leaking fluid begins?