According to the Centers for Disease Control and Prevention, 25 percent of pregnant women are carriers for Group B Streptococcus (GBS) bacteria. Because women who carry these bacteria are typically asymptomatic, proper screening is vital to preventing this bacterium from being passed to your baby during birth.
Around week 36, your healthcare provider will perform a simple diagnostic test to see if you are a carrier for GBS bacteria. The test—which is performed by taking a swab from your vagina and rectum—will then be sent off to a lab, and results should be available within 48 hours.
Because carriers for GBS run the risk of transmitting the bacteria to the infant during birth, it is important to take precautionary measures to keep your baby healthy. If your baby comes in contact with GBS, he or she could develop a number of infections, including meningitis and infant pneumonia.
If you test positive for GBS bacteria, you will be given intravenous antibiotics as soon as you go into labor. These antibiotics will kill off some of the bacteria that could be dangerous for your baby, reducing the risk that he or she will be exposed to the bacteria during birth.
Your healthcare provider may also choose to prescribe antibiotics during labor if any of the following occur:
- A positive test in previous pregnancies. Because of the transient nature of the bacteria, you should be tested during each pregnancy. If you were given antibiotics during a previous delivery, chances are your provider will administer them again even if you do not test positive at this time.
- Fever during labor
- Preterm labor. If your water breaks prior to 37 weeks, call your physician and go to the hospital immediately. In this instance, your provider may not have been able to check for the presence of GBS, so he or she may administer antibiotics as a precaution.
- Prolonged membrane rupture. You may be given intravenous antibiotics if your water has been broken for an extended period during labor.
- Urinary tract infection caused by GBS bacteria during pregnancy