Group B Strep During Pregnancy

Group B streptococcus, better known as group B strep or simply GBS, is a type of bacteria that usually does not cause serious illness in adults. Many people carry this bacteria without knowing it. If you test positive for GBS during pregnancy, it can be passed onto your baby if you give birth vaginally. To prevent your baby from getting GBS, your healthcare provider will treat your GBS during labor.

Find out more about GBS, how it’s treated during pregnancy, and what the symptoms of group B strep are in infants.

What Is GBS?

GBS is a bacteria commonly found in adults that usually does not cause illness or health problems. It can be found in the urinary tract, digestive system, and reproductive tract. Most people don’t even know that they have it.

About 25 percent of moms-to-be carry the GBS bacteria. In pregnant women, GBS can cause urinary tract infections, or an infection of the placenta, womb, and amniotic fluid.

Moms-to-be are routinely tested for GBS during pregnancy, because in some cases GBS can cause an infection that can be passed from the mom to her baby during a vaginal delivery.

How Group B Strep Is Contracted

Experts aren't sure how group B streptococcus is spread among adults, as it's not sexually transmitted, and it’s not spread through food or water. This type of bacteria seems to come and go naturally.

Even the healthiest of people can carry the GBS bacteria. You may carry it in your body for a short while, or you may have always had it.

Having GBS generally does not pose any harm, and will not make you feel ill, or even trigger any symptoms. In some instances, the bacteria may invade your system, causing an infection, which is then known as GBS disease. This is usually treated with antibiotics.

Getting Tested for Group B Strep During Your Pregnancy

As part of routine testing during your pregnancy, you will be tested for GBS in the third trimester, usually between 36 weeks and 38 weeks of pregnancy.

Your healthcare provider will swab your vagina and rectum, and send the samples to a lab for testing. After a few days, results will show whether you carry the bacteria or not.

Group B Strep Treatment: Antibiotics

Being GBS positive doesn’t mean that your newborn baby will be at risk of becoming sick from it. If your test results come back positive, your healthcare provider will likely give you intravenous antibiotics during labor. This can reduce the chance of you passing the bacteria onto your child if you have a vaginal delivery.

Keep in mind that treatment is not effective if given well before your baby’s birth, because the bacteria can regrow. The antibiotics need to be administered during labor to be effective, ideally for at least four hours before delivery.

Antibiotic treatment is not generally needed if you are having a cesarean section. However, it may be given if your water has broken or labor has begun before your scheduled surgery.

It’s important to know that the antibiotics you receive during labor can help prevent early-onset GBS disease in your baby, but not late-onset GBS disease. (Read more about the difference between early-onset and late-onset GBS below.)

The cause or causes of late-onset GBS disease aren't completely understood. That’s why it’s important to keep an eye out for the symptoms of GBS in your baby and to let your baby’s healthcare provider know right away if you see any of the signs.

How Group B Strep Can Affect Your Baby

If you have group B streptococcus and you give birth vaginally, your newborn may contract it as she moves through the birth canal. There’s a small chance your baby may become critically ill from the bacteria, which is why it’s important to get treatment for GBS (in the form of antibiotics during labor) if you test positive for it during your pregnancy.

Types of Group B Strep in Babies

There are two possible types of GBS infection in babies:

  • Early-onset infection. This means your baby will have gotten the infection at birth. Symptoms may start to appear within 12 to 48 hours.

  • Late-onset infection. This means your baby will have developed the infection a week to a few months after birth.

Symptoms of Group B Strep in Your Baby

If your newborn or infant has GBS disease, you may notice the following symptoms:

  • Fever

  • Feeding difficulties

  • Breathing difficulties

  • Irritability or lethargy

  • Bluish skin color.

If you notice any of these symptoms, let your baby’s healthcare provider know right away.

A GBS infection may lead to a more serious problem in your newborn, such as:

  • Pneumonia, an inflammation of the lungs

  • Bacteremia, an infection in the bloodstream

  • Sepsis, the body's extreme response to an infection

  • Meningitis, an inflammation of the membranes and fluid around the brain and spine.

Your baby’s healthcare provider will be able to diagnose and provide treatment for these conditions.

Treatment of Group B Strep in Babies

If your baby is diagnosed with either early-onset or late-onset GBS, your baby’s healthcare provider will administer antibiotics right away. Your baby may also be given oxygen and intravenous fluids.

Factors That Increase Your Baby’s Risk of Getting Group B Strep

There is an increased risk that your baby will develop GBS disease if

  • you carry GBS in your body

  • your baby was born prematurely

  • your water breaks 18 hours or more before you actually give birth

  • you have an infection of the placental tissues or amniotic fluid

  • the bacteria has been detected in your urine during this pregnancy or a previous one

  • your temperature is higher than 100.4 degrees Fahrenheit during labor

  • you previously delivered a baby who contracted GBS.


In adults, the group B strep bacteria may come and go naturally, which means you may have it at some point, and no longer have it later. If it turns into an infection, or if your baby develops an infection after being exposed to it, your healthcare provider will treat the GBS disease with antibiotics.

If you find out that you’re positive for the GBS bacteria, keep in mind that about a quarter of all moms-to-be have it. Your healthcare provider knows what steps to take to help prevent your baby contracting it. You’re in good hands!

While you’re here: Have you thought of ways you can save money and earn rewards on all the diapers you’ll be purchasing once your baby is born? With the Pampers Club app, you can turn diapers and wipes into rewards like cash back and coupons.

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