Chaunie Brusie, BSN, is a registered nurse with experience in labor and delivery, critical care, and long-term care nursing. She lives in Michigan with her husband and four young children, and is the author of the book “Tiny Blue Lines.”

Holding my breath, I peered over the chart where my doctor was flipping through my latest test results.

"So…" I ventured. "What's the verdict?"

She looked up at me with a shake of her head. "Looks like you're GBS-positive again," she replied. "You know what that means."

After three previous "GBS positive" pregnancies, I did know what that meant.

Group B Streptococcus, also known as GBS or B strep, is a type of bacteria that around 25 percent of women naturally carry in their vaginal, urinary tract, or rectal areas. In general, the bacterium is not harmful to the pregnant woman, but it does carry serious risks for the baby.

The Risks of B Strep

Group B strep can cause two different diseases in babies — one that is called "early onset," that occurs during the first week of life, and one that is called "late onset," which can develop through the first three months of a newborn's life. About 1,000 babies in the United States develop early-onset group B strep disease, and the rate is higher with premature and black babies.

The risk of the early onset form of the disease can be drastically reduced through testing pregnant women and treating them with antibiotics during labor so that they don't pass the B strep onto their babies. The CDC reports that women who test positive for B strep but receive antibiotics during labor have a 20 times reduced risk of passing the disease on to her baby than women who don't receive antibiotics. The risks of group B strep for a baby include:

  • miscarriage
  • stillbirth
  • premature delivery
  • sepsis (infection of the blood that can lead to death)
  • pneumonia
  • meningitis
  • cerebral palsy
  • deafness
  • blindness
  • learning difficulties

How Will I Be Tested?

All pregnant women are screened for B strep, usually at their first prenatal appointment, and again near the end of their pregnancy, around 35 to 37 weeks. B strep may come and go during your pregnancy, which is why it's important to test near the end, when you are closer to delivery.

To test for B strep bacteria, your doctor will simply use a small swab that looks like a long Q-tip to obtain a sample from the vaginal and rectal areas. If it's your first prenatal visit, you will most likely be getting a Pap Smear at the same time and won't even notice the testing. Your doctor may also test for B strep in your urine with the urine sample you provide at your visit.

What You Can Expect

If you test positive for GBS, you will be treated with antibiotics during labor, or prior to a C-section. According to the CDC, once group B strep shows up on your body, it's a sign of colonization, which means that pesky bacteria could pop up again at any time — posing potential risk for your baby.

Women experiencing premature labor may also be treated as if they have B strep as a preventive measure against an infection. For example, if you are admitted to the hospital with preterm labor and the staff is unsure of your B strep status, you may be given antibiotics just in case.

I'm Planning on a C-Section, Will I Need to Be Tested?

Yes, even if you're planning a C-section for delivery, you will need to be screened for B strep and treated if you register positive at any point during your pregnancy, just in case your water breaks or you have any other signs of premature labor that could put your baby at risk for infection.

B strep can be transmitted to the baby even if a woman's water doesn't break and she's not in labor, although the risk is much smaller than with ruptured membranes.

While You're in Labor

If you're delivering in a hospital or birth center, the treatment for B strep will barely be noticeable, since the antibiotics will be delivered through your intravenous (IV) line. Almost every woman during labor will have an IV line, so your OB nurse will simply hook up the antibiotic (usually penicillin, although if you're allergic, a different antibiotic will be used) right to your IV, typically every 6 to 8 hours until you deliver your baby. The antibiotics work to kill off some of the B strep bacteria to help decrease the chance of passing it your baby during labor and delivery.

After having antibiotics to ward off any effects of the group B strep during all four of my labors, I can safely say that I barely noticed the treatment. In a few instances, the antibiotic used was uncomfortable, but when I notified my nurse, she simply slowed down the rate at which the antibiotic was infusing and I was completely comfortable.

After Your Baby Is Born

Women who were positive for B strep during their pregnancies will need no special treatment or monitoring after they deliver their baby. However, some hospitals may monitor the babies of B strep-positive mothers more closely. At the hospitals I stayed in, for instance, my baby was required to stay a full 48 hours after my vaginal delivery to ensure that she didn't have a temperature that could signal the start of an infection from the B strep.

If you are delivering with a hospital and are unsure of what you can expect after your baby's birth, be sure to check with your doctor so you can plan your stay if you are B strep-positive.