Can an infection you don't even know you have be harmful to your baby? This scary prospect is a real one for almost one in every 1,000 U.S. newborns infected with Group B streptococcus (GBS). Although GBS is mainly a problem for newborns, it's also a common cause of postpartum uterine infections in women, resulting in fever, abdominal pain, and rapid pulse.

Between 10 and 30 percent of pregnant women have GBS in their vaginal or rectal area; each carries a one in 100 chance that her baby will become infected. Most people who harbor GBS aren't aware of it, because it rarely causes any symptoms. The bacterium lives in the gastrointestinal tract, along with numerous other bacteria that are harmless to most people. However, if GBS is absorbed by baby as he passes through the birth canal — for example, by ingesting vaginal fluids during delivery — it could make him very sick.

Strep in Newborns
There are two forms of GBS infection in infants:

• Early-onset: About 80 percent of newborn infections are early-onset, and these are almost always transmitted from mother to child during delivery. Babies with early-onset GBS develop symptoms within seven days of birth, usually within the first six hours of life. Early-onset infection could show up in your baby as a form of pneumonia, sepsis (blood infection), or, less commonly, meningitis (infection of the membranes surrounding the brain).
• Late-onset: Infections in babies seven days to three months old are considered late-onset. These infections are contracted either at delivery or after birth from an outside source, including family members, visitors, or hospital staff who didn't wash their hands thoroughly. Late-onset infection usually takes the form of sepsis or meningitis.

Fortunately, doctors have made progress in preventing early-onset Group B strep infection in newborns. According to a new study by the Centers for Disease Control and Prevention, the number of babies who developed early-onset GBS dropped 65 percent between 1993 and 1998.

What Can You Do to Prevent Strep During Pregnancy?
Your doctor will use one of two approaches to prevent Group B strep infections.

The first strategy involves screening expectant mothers for GBS during the last weeks of pregnancy. If you test positive for GBS, you will be treated with intravenous antibiotics — usually penicillin, or a related drug called ampicillin — during delivery. Antibiotic treatment can benefit mother as well as baby. A recent study shows that moms get fewer postpartum uterine infections associated with GBS when they're screened and treated for the bacterium before delivery.

Some doctors prefer another approach to treating GBS: bypassing the screening process and using antibiotics to treat only those expectant mothers who have risk factors for passing GBS on to their babies. Risk factors include:

• Previous birth of a baby with GBS infection
• Urinary tract infection caused by GBS during pregnancy
• Preterm labor (labor before 37 weeks of pregnancy)
• Premature rupture of the membranes (water breaking before 37 weeks of pregnancy)
• Prolonged rupture of the membranes (longer than eighteen hours spent in delivery)
• A fever of 100.4 degrees or higher during labor

While current methods of prevention can protect most babies from GBS infection, some newborns still get it. Researchers are seeking to develop a vaccine for expectant mothers that could prevent both early- and late-onset infections.

Richard H. Schwarz, MD, obstetrical consultant to the March of Dimes, is chairman of the department of obstetrics and gynecology at New York Methodist Hospital in Brooklyn, and a professor of obstetrics and gynecology at Cornell University Medical College in New York City.

The information on this Web site is designed for educational purposes only. It is not intended to be a substitute for informed medical advice or care. You should not use this information to diagnose or treat any health problems or illnesses without consulting your pediatrician or family doctor. Please consult a doctor with any questions or concerns you might have regarding your or your child's condition.

Content courtesy of American Baby.