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  • Topics >
  • Staying healthy while pregnant >
  • Prenatal Testing & Screening

Group B strep

Group B streptococcus — often called group B strep or GBS — is a common type of bacteria. When you think about bacteria you might immediately think, “Ick!” but this is a bacteria that occurs in the body naturally. These little GBS organisms typically live in the intestines and the urinary and genital tracts. 

The good news? Usually GBS doesn’t cause any symptoms or make you sick and can actually come and go, though sometimes it can lead to minor infections, like bladder or urinary tract infections (UTI). And, again, a lot of people carry Group B strep naturally — about 1 in 4 pregnant women carry GBS bacteria in the vagina or rectum — and you might never even know it until you get tested for it during pregnancy. 

A routine test during pregnancy, your healthcare provider will test you for GBS between weeks 35-37. A simple swab of your vagina and rectum will be sent off to a lab to tell you whether or not you have GBS. If you do test positive, you’ll be considered group B strep positive. 

The bad news? While being a carrier of GBS doesn’t impact your health much, it can cause problems if you pass the infection along to your little one during childbirth. (This can happen if, during a vaginal delivery, the baby is exposed to or swallows any fluids that contain the bacteria.) Some of these problems can lead to serious illness, like meningitis, pneumonia, or sepsis. Many babies who are treated for GBS do just fine, but because of the risks, it’s important to try to prevent newborns from getting GBS in the first place. 

More good news? If you do test positive for GBS, fortunately all it takes to help prevent Baby from being infected is an antibiotic that will be given to you during labor and delivery through an IV — usually penicillin or ampicillin. Because GBS can come and go — and can come back rather quickly — antibiotics need to be administered during labor and not before. This works best when treatment begins at least 4 hours before childbirth. If this happens, a baby then won’t likely need any extra antibiotics or treatment after birth. Because of the timing needed for antibiotics, this may impact when you need to go to the hospital while in labor or if your water breaks. Be sure to check-in with your provider about what they recommend for you, so that you can get the treatment you need in time.

Still more good news? If you test positive for GBS and get antibiotics during labor and delivery, there is only a 1 in 4,000 chance of passing along GBS to your baby, a much lower risk than if you test positive and don’t get antibiotics, which amounts to a 1 in 200 risk. If you do test positive for group B strep, don’t let it worry you much. Even if you are a carrier, having this knowledge is powerful, and, fortunately, makes it rather easy to help prevent GBS in your little one.

Reviewed by the Ovia Health Clinical Team


Read more

  • Rh factor during pregnancy: why you should know it
  • Building a birth plan

Sources

  • “FAQ105: Group B Strep and Pregnancy.” The American College of Obstetricians and Gynecologists. American College of Obstetricians and Gynecologists, September 2017. Retrieved December 15 2017. https://www.acog.org/Patients/FAQs/Group-B-Strep-and-Pregnancy. 
  • “Group B Strep (GBS): Prevention in Newborns.” Centers for Disease Control and Prevention. U.S. Department of Health and Human Services, May 23 2016. Retrieved December 15 2017. https://www.cdc.gov/groupbstrep/about/prevention.html.
  • “Group B strep infection.” March of Dimes. March of Dimes Foundation, November 2013. Retrieved December 15 2017. https://www.marchofdimes.org/complications/group-b-strep-infection.aspx.
  • “Group B Strep (GBS): Fast Facts.” Centers for Disease Control and Prevention. U.S. Department of Health and Human Services, June 15 2016. Retrieved December 15 2017. https://www.cdc.gov/groupbstrep/about/fast-facts.html.
  • Mayo Clinic Staff. “Group B strep disease.” Mayo Clinic. Mayo Foundation for Medical Education and Research, April 26 2016. Retrieved December 15 2017. https://www.mayoclinic.org/diseases-conditions/group-b-strep/symptoms-causes/syc-20351729. 
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