You’ve reached the home stretch, your 36th week. All you have to do is sit back, put your feet up, and wait for labor to start, right? Not exactly. First, do you know what your group B strep status is?
“It’s extremely important that every pregnant woman knows her beta strep status before she goes into labor,” says Randy Fink, M.D., an ob/gyn in private practice in Miami. “If your doctor doesn’t test you, go to someone who will.”
What is group B strep?
Group B strep—also known as GBS, beta strep, or, more formally, group B streptococcus—is a very common bacteria found in the vagina or lower intestine of many healthy adult women. “I like to stress that a positive test result is extremely common,” Fink says.
“Unfortunately, when patients hear they tested positive, they think they’ve contracted a terrible disease. It’s simply bacteria,” Fink continues. “It’s not considered a sexually transmitted disease, though it is common in sexually active people.”
And even if you test positive, you’re not sick. “Group B strep is not an infection,” says Ralph Dauterive, M.D., chairman of obstetrics and gynecology at Ochsner Clinic and Foundation in Baton Rouge, LA. But if you’re not sick, why is knowing your status so important? Do you really need another pregnancy test so late in the game?
The answer is a resounding yes. “The problem isn’t the bacteria,” Fink explains. “The problem is the risk associated with the bacteria.” That risk is group B strep disease—the most common cause of life-threatening infections in newborns, according to the Centers for Disease Control and Prevention (CDC).
How can it affect my baby?
If a mother tests positive for group B strep, her baby can be exposed to the bacteria while passing through the birth canal. Exposure can result in one of two types of group B strep disease. “Early-onset disease” happens within the first week of life and is often noticeable within the first few hours out of the womb. Babies with early-onset disease can develop a variety of illnesses, including pneumonia, sepsis (a blood infection), and meningitis.
“Late-onset disease,” on the other hand, develops in infants between 1 week and 3 months of age. This group is more likely to develop meningitis, however, late-onset is also less common.
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If GBS is present in the vagina or rectum at the time of delivery, there is only a 1-in-100 chance that baby will become sick. The odds increase with certain risk factors, including water broken more than 18 hours before birth, delivery before 37 weeks, or a fever over 100.4°F during labor. Some babies may be born with the bacteria on their skin, but most will not develop the infection.
“Transmission to the fetus is very low, and infection rates are even lower,” Dauterive says. “Remember to keep things in perspective.”
Testing and treatment
Fortunately, screening for group B strep is easy. “It’s simply a swabbing of the vagina, perineum, and rectal area, done at 35 to 37 weeks of pregnancy,” Fink says. Most care providers will have your results before your next visit. The procedure is relatively painless, and knowing the outcome is important for both the mother and child.
If the results are positive, there’s no need for concern. You’ll receive an antibiotic in your IV during labor. “Three doses of penicillin or a similar antibiotic before the baby is born is ideal,” Dauterive says. Because you never know how long your labor will last, make your status known when you get to the hospital to ensure you’ll get as many doses as possible.
Taking the antibiotics during labor is the best way to control the bacteria during the child’s birth. A recent CDC study indicates that this approach may prevent almost 90 percent of early-onset disease.
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Of course, there are times when labor is premature or goes so quickly that the mother is unable to receive the recommended antibiotics. In those cases, the baby is monitored after birth, Dauterive says.
Remember that although the complications attributed to group B strep are serious, they’re extremely rare. “Group B strep in itself is not a terrible disease,” Fink says. “It’s simply a bacteria that lives in many people.”
What about c-sections?
If the real danger is baby’s exposure to group B strep in the birth canal, why not skip that step completely and schedule a C-section for moms-to-be with a positive status?
“Unfortunately, a Cesarean section does not totally eradicate the risk of group B strep,” says Randy Fink, M.D. “Sometimes the bacteria can transport up into the -vaginal cavity, particularly if the water is already broken.” If a C-section is necessary for a safe delivery, you’ll still receive penicillin or other antibiotics if you tested positive for GBS.
Mary Dixon Lebeau took so many tests during her five pregnancies, she felt like a lab rat—but it was worth the trouble to know she was GBS positive before delivering her youngest. Lebeau’s work also appears in Parenting and Conceive magazines.