Group B Strep (GBS) In Pregnancy: Symptoms, Treatment And Prevention

Group B Strep (GBS) In Pregnancy Symptoms, Treatment And Prevention-1

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Group B streptococcus (GBS) is one of the most common bacterial species found in pregnant women. The bacteria usually inhabit their gastrointestinal and reproductive tracts. Statistics show that an estimate of 25% of women carries group B strep in their rectal and vaginal areas (1). However, this does not cause any harm to a pregnant woman’s health and may not show any symptoms in most cases.

Although not common, group B strep might cause infections if left undiagnosed and untreated. It can therefore affect the mother’s health during pregnancy and postpartum
(1) (2).

Read through the post to know the causes, symptoms, and treatments of group B strep pregnancy.

What Are The Symptoms Of Group B Strep Infection?

The manifestation of the disease varies from person to person depending upon the type of infection caused by the group B strep bacteria.

Newborns or infants who have contracted this bacteria can show the following symptoms (2) (3):

  • High body temperature
  • Limpness and minimal body movements
  • Feeding problems
  • Breathing difficulties

Generally, pregnant women giving birth to a GBS-affected baby may not show any bacterial symptoms themselves.

How Does Group B Strep Affect Pregnancy?

In most cases, group B strep might not show any symptoms or pose any threat to a pregnant woman’s health. However, in rare circumstances, it may lead to some morbidities (4) (5) (6).

  • Chorioamnionitis: A breakage in the amniotic sac or a membrane rupture can cause GBS infection in the amniotic fluid and the placental tissues. This will, therefore, lead to chorioamnionitis.
  • Urinary tract infection (UTI): One of the common infections caused by the group B strep bacteria, which can lead to premature birth.
  • Sepsis: Group B strep can cause blood infection in a pregnant woman. It is one of the rarest and most serious infections that could occur during pregnancy from GBS.

How Does Group B Strep Affect A Newborn?

A group B strep-positive mother can transfer the bacteria through the genital tracts during labor and delivery. According to the CDC, the probability of newborns getting GBS-induced disease is one in 4,000 if the mother has received the antibiotics and one in 200 if she has not received antibiotics during delivery or labor (7).

The infections in newborns are divided into two categories (8) (9):

  • Early-onset infections: About 75% of the newborns contract GBS in their first weeks of life, called early-onset disease. The baby may start showing symptoms within the first 24 hours or up to the first seven days following delivery. The infections are sepsis (blood infection), pneumonia (lung infection), and meningitis. Premature babies experience higher risks since they have weaker immune systems. Around 4% to 6% of infant deaths might occur from early-onset GBS infections.
  • Late-onset infections: These are rare where the symptoms may take more than a week or few months to appear. Meningitis is the most observed group B strep infection.

Newborns may have contracted the bacteria from the mother during birth, but late infections can also occur from GBS transfer from another GBS-positive person. However, the exact cause of late infection is still not determined. Late-onset infections hold a lesser probability of infant deaths than early infections.

How Is Group B Strep Diagnosed?

Diagnosis involves a routine screening for GBS between 35 and 37 weeks of pregnancy. Your health care provider will culture the bacteria from rectal and vaginal swabs(4). Upon positive results, the required treatment is administered. Sometimes, urine tests during pregnancy are also carried out to rule out the possibility of UTI caused by GBS (9).

How Is Group B Strep Treated?

Antibiotics, mainly penicillin G and ampicillin are the suggested treatment for Group B strep infections and prevent its transfer to the newborn from the mother. These are administered intravenously four hours prior to delivery and throughout labor. Alternatively, vancomycin is administered for those allergic to penicillin (10).

For newborns showing GBS, the doctor will provide a similar IV drip treatment of antibiotics in labor.

Note: In cases of C-section delivery, the affected pregnant women may not require antibiotics treatment unless the labor begins or waters break. It is because the bacteria can only get transferred to the newborn through genital tracts.

How Can You Prevent Group B Strep Infection?

There is no vaccine available for preventing group B streptococcus infections. However, certain preventive measures help minimize the risk of GBS infection.

    • Testing the pregnant women to determine the presence of GBS through a vaginal and rectal swab (during 35 to 37 weeks).
    • Administering antibiotics during labor until delivery and not earlier since the bacteria may recolonize the genital tract during labor (11).

In case of negative results and the following conditions, the doctor may consider GBS treatment to prevent further transfer of infection (12):

  • Fever at the time of labor
  • Premature delivery
  • Frequent urination or burning sensation during peeing

Note: Despite the above preventive measures, one may still get GBS. Researchers are working towards finding a definite treatment and vaccination for group B strep.

Can GBS Affect Future Pregnancies?

Yes. If you have been diagnosed with group B strep in your last pregnancy or have given birth to a child with GBS, you may be at a higher risk of developing GBS infection in your future pregnancy. Let your doctor know about your past GBS infections, if any, to avoid complications (12) (8).

Frequently Asked Questions

  1. Does strep B go away?

Group B strep is a common bacterium in the body and can naturally go away without causing any symptoms (2). An estimate of a 90% prevention rate is observed with antibiotic treatment (9).

  1. Is strep B an STD?

No, group B streptococcus is not a sexually transmitted disease. It is mostly transferred from the mother to the baby during labor or delivery (8).

Group B streptococcus is typically harmless and may cause serious infections in rare circumstances. Simple IV drip antibiotic treatment can treat infections and prevent the transfer of the bacteria to newborns. However, in case of complications, additional treatments may be suggested by your healthcare provider.


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Aneesha Amonz

Aneesha holds a Bachelor's degree in Biotechnology from USTM, Meghalaya and Master’s degree in Applied Microbiology from VIT, Vellore. She has worked on different research projects in the field of Food Sciences. In addition, she has an internship experience in Oil India Limited as an R&D project trainee. As a writer at MomJunction, Aneesha ensures her content is engaging and... more