What causes group B strep in pregnancy?

The bacterium can live in the bowel and sometimes the vagina without causing illness. Carriage is not caused by poor hygiene, and it is not generally treated as a sexually transmitted infection. It may be present on one test and absent on another because colonisation can change over time.

A positive swab or urine result indicates that the bacterium was detected, not that you are ill. The concern in pregnancy is that a baby can encounter group B strep around labour and birth and, in some cases, develop a serious infection.

A urine infection caused by group B strep is different from symptom-free vaginal or rectal carriage and needs clinical treatment. Your maternity team records the result because it can affect the antibiotic plan for labour and the observation plan after birth.

Tell your maternity team about any positive group B strep result in this pregnancy and about serious antibiotic allergies. When antibiotics during labour are recommended, they are given into a vein after labour begins or the waters break; taking routine antibiotics earlier does not reliably remove carriage until birth.

Follow the testing approach offered by your clinician, because local protocols and individual circumstances shape the plan. Keep a copy of relevant results and make sure the intended birth setting knows about them.

Contact your maternity unit when labour begins or your waters break if group B strep has been identified or antibiotics in labour were advised. Seek prompt assessment during pregnancy for fever, painful urination, flank pain, leaking fluid, reduced fetal movement or feeling markedly unwell.

After birth, urgent newborn assessment is needed for poor feeding, unusual sleepiness, breathing difficulty, abnormal temperature, grunting, colour change or a baby who is difficult to wake. These signs have several possible causes but should not be watched at home.

Ask whether your result represents carriage or a urine infection, whether antibiotics during labour are recommended, and when you should come to hospital after contractions or broken waters begin. Clarify which antibiotic can be used if you have an allergy and how your baby will be observed after delivery.