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What to Know About Group B Strep During Pregnancy
August 7, 2023

What to Know About Group B Strep During Pregnancy

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What to Know About Group B Strep During Pregnancy.
What to Know About Group B Strep During Pregnancy

Pregnancy brings with it a treasure trove of health conditions you’ve probably never heard of before—Group B strep may be one of them. So what is it exactly? And why does it matter in terms of pregnancy? Here’s everything you need to know.

What is Group B Strep?

Group B Streptococcus (also called group B strep, or GBS) is a type of bacteria that naturally lives in our bodies, specifically in our intestines and the urinary and genital tracts. It’s also very common—about one in four pregnant people carry the bacteria.

If you’re a healthy adult, you don’t need to worry about GBS—it comes and goes on its own and is usually harmless. Most people won’t even know they have GBS, since you won’t have signs of infection unless it finds its way into your bladder (at which point you may begin having symptoms of a urinary tract infection). “If one has an infection with GBS in their bladder (a urinary tract infection, or UTI), they will probably feel an urgency to urinate but not much urine coming out, burning while urinating or possibly aching around the pubic bone,” says Evaly Long, a licensed midwife with Hummingbird Midwifery. UTIs caused by GBS are easily treated with a course of oral antibiotics.

Unlike the flu (or even the common cold), a group B strep infection isn’t something you can catch by being around another person who has it, with one exception: “GBS can be passed back and forth between sexual partners,” says Long. And while it’s possible to pass it to someone during sex, it’s not considered a sexually transmitted infection.

If you’re pregnant, however, GBS is something to be aware of because it can be passed along to your baby during delivery and potentially make them sick. This is why routine testing for GBS during pregnancy is important, as well as having the proper treatment plan in place during delivery if you test positive.

What is the Group B Strep Test?

Here’s some good news: the group B strep test is a routine test that’s quick, easy and painless, and typically takes place between 35.

Your healthcare provider will test you by taking a swab of your vagina and your rectum during one of your regular exams. The sample will be sent to a lab, and your results will usually be available in a few days. In the case of an early or unexpected delivery, it’s also possible to do several quick screening tests while you’re in labor—but this shouldn’t take the place of the standard GBS test if possible.

What are the symptoms of group B strep?

Most people who test positive for GBS won’t show any symptoms—the positive test simply indicates that you’re a carrier, not that you’ll necessarily pass it along to your baby. But there are some symptoms that may mean you’re at a higher risk of delivering a baby with group B strep. They include:

  • A previous baby with GBS
  • Fever during labor (100.4 F or higher)
  • Urinary tract infection that’s a result of GBS during your pregnancy
  • Preterm labor (prior to 37 weeks pregnant) and/or water breaking
  • Water breaking 18 hours or more before delivery
  • An infection of placental tissues and amniotic fluid

You’re also at an increased risk for group B strep if you have a medical condition that affects your immune system, such as diabetes, HIV, liver disease or cancer.

If you’re a carrier for GBS while in labor and you’re not treated, there’s a 1-2% chance that your baby will get the infection. If you have the above risk factors/symptoms, the chance of infection in your baby is slightly higher.

What is the treatment for group B strep?

More good news here—the treatment for group B strep is simple and very effective.

If you’ve tested positive for the bacteria, you’ll receive antibiotics during labor through an IV. “Typically this antibiotic is Penicillin unless one has an allergy,” Long says. It’s recommended that the antibiotics are given at least 4 hours before delivery so they have time to begin working, then every four hours during active labor until your baby is born. This is why, as soon as you’ve been checked into the hospital, you’ll likely be hooked up to an IV to administer the antibiotics.

If you’re a group B strep carrier and you’re having a scheduled c-section birth before labor starts and before your water breaks, you most likely won’t need any medication, but you should still discuss your treatment plan with your doctor just to be sure.

How does group B strep affect baby?

Before you add this to your list of worries, it’s important to point out that with the right treatment, the statistics around properly treating and preventing your newborn baby from contracting group B strep are very much in your favor.

A pregnant person who tests positive for GBS and gets antibiotics during delivery has only a 1 in 4,000 chance of delivering a baby who will contract the bacteria. But if baby does get GBS, here’s what to know.

There are two kinds of GBS in babies: early-onset and late-onset.

Early-onset GBS presents within the first week of life and accounts for about half of all GBS infections in newborns. Long explains the symptoms to look for:

  • Continuous grunting
  • Flaring their nostrils
  • Rapid breathing (more than 60 breaths per minute)
  • The area around their nose and mouth turning blue (a serious sign that baby isn’t getting enough oxygen)

Babies with a GBS infection are usually treated with IV antibiotics in the newborn intensive care unit. When left untreated, GBS infection can cause pneumonia, sepsis or meningitis (an infection of the fluid and lining around the brain).

Signs of late-onset GBS generally begin between seven days and three months after birth and include symptoms like:

  • Coughing and congestion
  • Trouble eating
  • Fever
  • Drowsiness
  • Seizures

Late-onset can also cause sepsis and pneumonia, which is why early visits to your pediatrician are important.


Evaly Long, CPM, LM, of Hummingbird Midwifery.

Babylist Staff

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