When should the test for group B strep be performed?
There are two recommended approaches to the GBS problem. • Cultures for GBS are taken from all pregnant women at 35 to 37 weeks of pregnancy. The test is a vaginal and rectal swab which you or your doctor can perform. All women who test positive for GBS are then given intravenous antibiotics in labour (usually ampicillin but clindamycin if you are allergic to penicillin). The antibiotics are most effective if they are in your system for at least four hours before the baby is born. • Another approach is not to screen mothers with a swab but to give the intravenous antibiotics to all labouring women who have a high risk situation for GBS infection in the baby. These high risk situations include: • premature labour (before 37 weeks), • prolonged rupture of the membranes (waters broke more than 18 hours ago), • fever in the mother during labour • women who have had other newborns with GBS infection • GBS infection in the urine.
