Antibiotics for group B strep during labor

Treatment is usually started when labor begins or the waters break and continued at regular intervals until birth. Penicillin is commonly used, but the maternity team can select another antibiotic when an allergy or another clinical factor makes that necessary.

Group B strep, often shortened to GBS, is a bacterium that can live in the bowel or vagina without causing illness. During birth, it can pass to a newborn and occasionally cause a serious infection. Antibiotics in labor lower exposure around the time of delivery; they do not mean that the pregnant person is unwell or has a sexually transmitted infection.

A positive screening result describes colonisation at the time of testing. Taking oral antibiotics earlier in pregnancy does not reliably keep GBS away until birth, which is why preventive treatment is timed to labor. The baby's clinical team may adjust observation after delivery according to when treatment began, the birth circumstances, and how the baby is doing.

Tell your maternity team that you have had a positive GBS result, GBS found in urine, or a previous baby affected by GBS infection. Keep the result available with your pregnancy notes, and make sure any medication allergy is recorded with details of the reaction rather than only the drug name.

Contact the maternity unit promptly when contractions suggest labor or when your waters break, following the plan they gave you. At the hospital, the antibiotic is delivered through a cannula in a vein. Care should not be delayed solely to complete a planned course if birth is progressing quickly; the obstetric and newborn teams will manage the situation based on the time available.

Call your maternity unit without waiting if your waters break, labor starts, you develop fever or feel acutely unwell, or your baby's movements are reduced or have changed from the usual pattern. These signs need maternity assessment regardless of the GBS result.

While receiving an antibiotic, immediately alert staff about trouble breathing, swelling of the lips, tongue or throat, widespread hives, dizziness, or a feeling that you may faint. These can indicate a severe allergic reaction and require urgent treatment.

Ask which antibiotic is planned, when you should come to the maternity unit, and how a known allergy changes the choice. You can also ask what monitoring your baby may need if labor is rapid, antibiotics start shortly before birth, or a planned caesarean changes unexpectedly after labor or membrane rupture begins.