Group B Strep (GBS)

A common bacteria that many women carry, which requires antibiotics during labor to protect the baby.

What is Group B Strep (GBS)?

Group B Streptococcus (GBS) is a common type of bacteria that is often found in the digestive tract and the vagina. It is not a sexually transmitted infection, and for most healthy adults, it causes no symptoms or issues whatsoever.

However, GBS can be dangerous for a newborn if it is passed to them during a vaginal delivery.

The GBS Screening

Because GBS status can change, doctors perform a routine screening between 36 and 37 weeks of pregnancy.

• The Test: A simple swab of the vagina and rectum.
• The Result: If the test is positive, you are a 'GBS carrier.' This is not a cause for alarm—about 1 in 4 pregnant women are carriers.

Why it Matters for Birth

If you are GBS positive, the standard medical protocol is to receive intravenous (IV) antibiotics (usually penicillin) during labor.

• Timing: The goal is to get at least one dose of antibiotics four hours before the baby is born.
• Protection: This simple step reduces the risk of the baby developing a GBS infection (which can lead to pneumonia or meningitis) from 1 in 200 to 1 in 4,000.

What if I Have a C-Section?

If your water hasn't broken and you haven't started labor, a scheduled C-section usually does not require GBS antibiotics, as the baby does not pass through the birth canal where the bacteria live.

The Bottom Line

GBS is a perfect example of why modern prenatal care is so effective. A simple swab and a quick dose of antibiotics are all it takes to keep your newborn safe from a preventable complication.