After 35 weeks into the pregnancy, we recommend for all obstetrical patients to be cultured for GBS, a common type of bacteria in their normal flora that does not cause any problems. Up to 40% of people are colonized normally at various times in their lives with this GBS bacteria as a part of the body flora. GBS is not a disease and does not usually cause any illness.
Your doctors are testing GBS around the time of delivery to avoid passing the bacteria to the newborn baby at birth. Only 1 to 2 of every 100 babies born to moms who are GBS positive can get a newborn infection. The newborn could get an immediate early infection within the first 6 hours of birth or less commonly a late infection after the first 7 days of delivery. Although most infections are treatable with antibiotics, about 5% of the infected babies have the risk of death or 2 out of 1,000.
The GBS culture is taken from the perineum (the vulvar area) and opening of the rectum after 35 weeks of pregnancy. If you do have a positive culture, we will identify this on your medical records and inform you that when you come in to the hospital in labor that (IV) intravenous antibiotics will be given to you before delivery. If you are one of our fortunate patients with fast labors, you may need to check in early just to allow enough time to get antibiotics. The good news is that the rates of infection are lower among women whose membranes are not ruptured long and have short labors.
We also recommend the use of antibiotics in women “at risk for GBS”. The group includes preterm labor 37 weeks, premature rupture of membranes, prolonged (> 18 hours) rupture of membranes, a prior baby with a GBS infection, or a history of a urine culture that was positive for GBS.
The latest recommendation for women who are scheduled for an elective Cesarean Section is that treatment is not needed unless your membranes are ruptured or you have labor contractions at the time of surgery.
Please inform us if you have any drug allergies. The first line of treatment used at our hospital is Ampicillin. If you are allergic to penicillin type antibiotics, we will give you Clindamycin (7-14% resistance). If your allergy is mild and you have been tested to tolerate Cefazolin, we prefer this as the second line medication. Rarely, the 3rd line choice for a documented susceptible, allergic patient is Vancomycin.
Your doctors encourage you to do the culture but not to worry about being GBS positive since so few babies actually get sick. Since this protocol to treat GBS has been established in our practice and hospital, we have not had any sick baby due to GBS.
