Pregnancy Spotlight: Group B Strep

Every day, our nurses and attorneys receive calls from expectant mothers with concerns about symptoms they’re experiencing during their pregnancy. They’re curious if their symptoms are normal, and they wonder what their next steps should be. Patients should always visit a medical professional with concerns like these and receive appropriate care for maternal-fetal conditions and illnesses that can arise during pregnancy. We kickstarted the Pregnancy Spotlight Series, a monthly column that highlights specific pregnancy health concerns to empower patients in contacting their medical providers.  Today, we’re focusing on Group B Strep (GBS).

What is Group B Strep?

Group B Streptococcus (Group B Strep, GBS) is a common bacterium found in the lower genital tract or the intestines. It is normally harmless for adults, but it can cause serious infection in nonpregnant adults, pregnant women, and newborns. When Group B Strep passes from the mother to the newborn before or during delivery, it can lead to Group B Strep Disease.

How common is Group B Strep?

Pregnancy Spotlight - Group B Strep - Reiter & Walsh Presence of the Group B Strep bacterium is quite common in healthy, adult women (about 25% of women have it in their rectum or vagina). A mother can pass this bacteria onto her baby during delivery. This can lead to serious infection and injury to the baby.  Not every baby born to a mother with GBS will be affected by it, however. Moreover, in the United States, GBS affects 1 in every 2,000 babies.

How do I know if I have Group B Strep?

Your doctor will screen you for Group B Strep between weeks 35 and 37 of your pregnancy. The screening involves taking a swab test from the rectum and the vagina and analyzing the culture for the presence of the Group B Strep bacterium. GBS infection sometimes does not have signs or symptoms, so clinical testing is very important.

How can I know if my baby has Group B Strep Disease?

According to the Center for Disease Control and Prevention (CDC), there are two types of Group B Strep Disease that can occur in newborns, early-onset and late-onset GBS.

Early-onset occurs during the first week of the newborn’s life and is usually a result of the infection being passed from mother to child during delivery.  

Late-onset can occur between the first week and 3 months of the newborn’s life. It can also result from bacteria that is passed between mother and child during delivery, but it can be contracted in other ways as well.

What are the signs and symptoms of GBS?

Symptoms of early-onset and late-onset GBS Disease may include:

  • Lethargy
  • Difficulty Feeding
  • Fever
  • Temperature instability
  • Irritability
  • Bluish skin color
  • Seizures

How can my baby be diagnosed with Group B Strep Disease?

If the mother tested positive for Group B Strep and received antibiotics during delivery, the baby will be checked for GBS shortly after birth. The baby will be likely provided with prophylactic antibiotics to prevent infection of the membranes surrounding the brain and spinal cord.

If the doctor suspects early-onset or late-onset GBS, the doctor will likely test the baby’s spinal fluids or blood for the disease. They can also take a chest x-ray to confirm the diagnosis. Doctors should not delay giving antibiotics for imaging studies or testing if infection is suspected, because infections of the blood,  brain and spinal cord can cause brain damage, seizures, cerebral palsy, as well as intellectual and developmental disabilities if not treated promptly.

How will the baby be treated for Group B Strep Disease?

Doctors will treat GBS in babies with antibiotics like ampicillin and penicillin through an IV. If the disease is more severe other treatments will be necessary.

What complications can Group B Strep Disease cause for my baby?

Early-onset Group B Strep Disease can cause such complications as pneumonia, sepsis, and meningitis. Late-onset Group B Strep Disease can cause these complications as well, but meningitis is more common with late-onset than early-onset GBS. Long-term issues such as developmental and intellectual disabilities as well as  deafness and cerebral palsy can occur in babies who have early-onset or late-onset GBS (especially when accompanied by meningitis).

How can I prevent Group B Strep Disease in my baby?

The best prevention for GBS Disease in the baby is for doctors to treat  mothers who test positive for GBS with  IV Antibiotics during labor and delivery.

Antibiotics during delivery: Antibiotics (normally penicillin) help kill the Group B Strep bacteria that are harmful to the baby. The bacteria can grow back quickly, so the only way to stop them from passing to the baby during delivery is to administer antibiotics during delivery. These antibiotics are usually given once labor has begun and every four hours of active labor after that.

What makes me high-risk for passing GBS onto my baby?

According to the CDC, the following circumstances place you at a higher risk of passing your GBS onto your baby:

  • An early delivery (before 37 weeks)
  • Having a previous baby who developed early-onset GBS
  • Experiencing a long duration between your water breaking and delivery (18 hours or more)
  • Testing positive for Group B Strep bacteria late in pregnancy (35-37 weeks)
  • Detection of Group B Strep bacteria in urine during pregnancy
  • Developing a fever during labor

Your doctor should counsel you about the risk of your baby developing Group B Strep infection during your third trimester.

Related Resources on GBS


The information presented above is intended only to be a general educational resource. It is not intended to be (and should not be interpreted as) medical advice. If you have questions about the topic, please consult with a medical professional.

Share This Post

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply