What happens if you have group B strep during pregnancy?

What is group B strep?

Group B streptococcus (GBS) is a kind of bacteria that many people naturally have in their intestinal tract.&

The bacteria may also inhabit, or "colonize," your vagina and be passed on to your baby during labor and birth. Experts estimate about 25% of women carry group B strep, though very few babies get sick with GBS disease. (This bacteria is not the same as group A strep, the type that usually causes strep throat.)

It's possible to spread group B strep through sexual contact, but it's not considered a sexually transmitted infection because your genital area may be colonized by bacteria you carry in your own gastrointestinal tract.

Why do I need to be tested for group B strep when I'm pregnant?

Although group B strep is generally harmless to healthy adults, it may cause stillbirth and serious infections in babies. Getting screened for group B strep late in pregnancy – and being treated with antibiotics during labor if you test positive – greatly reduces your baby's risk of becoming infected.

That's why the U.S. Centers for Disease Control (CDC), the American Academy of Pediatrics (AAP), and the American College of Obstetricians and Gynecologists (ACOG) recommend that all pregnant women get a routine group B strep screening at 36 to 37 weeks.

The test isn't done earlier because you'll only be treated for group B strep during labor to protect your baby. If you're given antibiotics to combat GBS earlier, there's a chance the bacteria can grow back before you go into labor – and then your baby wouldn't be protected.

You'll be treated during labor if you're at high risk for group B strep. Risk factors include:

• A positive test for group B strep at any time during your pregnancy.
• A urinary tract infection (UTI) caused by group B strep or a urine culture with group B strep at any time during your pregnancy.
• A previous baby with GBS disease.

"You can be positive in one pregnancy and negative in the next one," says Layan Alrahmani, M.D., an ob-gyn, maternal-fetal medicine specialist, and member of BabyCenter's Medical Advisory Board. "This is the reason why we check it every pregnancy."

How is the GBS test done?

Toward the end of your pregnancy, your healthcare provider will painlessly swab the lower end of your vagina and rectum. The sample is sent to a lab to be grown in a culture, which will identify whether group B strep is present. Results are typically available in two to three days.

Some hospitals offer rapid group B strep tests that can be done during labor, with results available in an hour or so. But the rapid tests are not as sensitive as those that allow time for the group B strep to incubate, so experts still recommend screening at 36 to 37 weeks.

What happens if I test positive for group B strep when I'm pregnant?

A positive result just means that you carry the bacteria, not that you or your baby will get sick, so try not to worry.

There's only a small chance that your baby will get sick, especially if they're full-term, you don't have a fever, and your water didn't break very long before delivery.

"It's nothing to be worried about," says BabyCenter Community member HolaMrsMartinez. "It's important to know about GBS before attempting a vaginal birth, so that your baby is protected from the bacteria as they make their grand entrance! I'm just bummed to need an IV during labor."

Getting antibiotics during labor greatly reduces the chance that your baby will be infected. For example, if you're a GBS carrier with no other risk factors, your baby's odds of getting infected are about 1 in 200 without treatment, and about 1 in 4,000 if you get treatment.

Treatment also reduces your own chances of developing a GBS infection (such as a uterine infection) during labor or postpartum.

If you test positive for group B strep, you'll be given IV antibiotics as soon as active labor begins or your water breaks, whichever comes first. If you have a C-section, you'll be given antibiotics anyway, and these antibiotics will be adequate to treat the group B strep.

Ideally, you'll start antibiotics at least four hours before you give birth. If your labor is faster than that, even a couple of hours of antibiotics reduces the risk to your baby.

What could happen to my baby if they get GBS disease?

Early-onset GBS disease can cause an infection in the blood (sepsis) and pneumonia, and is a leading cause of meningitis in newborns. Some babies, especially those with meningitis, will have long-term health problems, such as hearing loss or vision loss, cerebral palsy, or developmental disabilities. A small percentage won't survive.

Preterm babies have a lower survival rate than full-term babies, and those who survive are at higher risk for long-term problems from the disease.

What if I have a UTI that's caused by group B strep during pregnancy?

If a urine test shows that you have a urinary tract infection caused by a certain level of group B strep (more than 100,000 "colony forming units," or CFU), you'll be treated with oral antibiotics. CFU levels over 100,000 are also linked with preterm labor. Because antibiotics decrease bacteria, they lower this risk in addition to treating the UTI.

Once you're done taking the antibiotics, you'll have another urine culture to make sure the infection is gone – just as with any UTI during pregnancy.

Although oral antibiotics will decrease the bacteria in your urinary tract, some bacteria may remain in your genital area or return there later.

Having group B strep in your urine is a sign that you have a lot of it in your genital tract, so you'll automatically be given IV antibiotics during labor.

What if I go into labor before my group B strep results are available?

If your test results haven't come back yet and you don't have any risk factors, your labor will proceed like normal and you won't be treated for GBS.

If you do have one or more of these uncommon risk factors, your healthcare provider may treat you with antibiotics during labor:

• You go into preterm labor, or your water breaks before 37 weeks.
• There's a long delay (18 hours or more) between your water breaking and your delivery.
• You develop a fever during labor (100.4 degrees Fahrenheit or higher).

If a rapid test is available and you don't have any risk factors, your provider may prefer to do the test and then treat you if the results are positive. (If the rapid results are negative but you go on to develop risk factors, you'll be treated anyway, since the rapid test may miss some GBS cases.)

What are the risks or side effects from taking antibiotics during pregnancy?

Penicillin is the most common antibiotic given to treat group B strep, and is considered safe to use during pregnancy. About 10% of pregnant women experience mild side effects from penicillin, such as a rash.

So if you're allergic to penicillin, let your healthcare provider know before they begin treatment. Other antibiotics are also effective and safe for your baby.

If I test positive for group B strep, what will happen after my baby is born?

If your healthcare provider has any concern that your baby is infected with group B strep (because you have an infection at delivery or because your baby has a fever), they'll start them on antibiotics immediately after delivery and order a full workup, including blood tests.

If your baby is having difficulty breathing, a chest X-ray will be done. And if your baby has a fever that doesn't go away, a spinal tap may also be ordered.

If your baby shows no signs of infection, you can usually take them home after a day or two.

If you'd like to go home earlier than that, your baby's healthcare provider may agree to discharge them after 24 hours as long as:

• You received antibiotics at least four hours before birth.
• You had no signs of infection during labor.
• Your baby is full-term, appears healthy, and has no other problems.
• You fully understand your provider's instructions for observation at home.
• You have quick access to medical care.

Otherwise, your baby will remain in the hospital for at least 48 hours for observation.

If your baby is born prematurely, they'll probably have some testing done and may need to stay longer, even if you were treated during labor and they show no signs of infection. This is because premature babies are more likely to get GBS disease and tend to be sicker if they do get it.

What are the symptoms of a group B strep infection in an infant?

If you're a GBS carrier, your baby will be observed closely for signs of infection – regardless of whether you were treated with antibiotics during labor.

Studies show that 90% of babies who get early-onset GBS disease begin to show these signs of sickness within the first 24 hours of life:

• Difficulty breathing
• Turning blue
• Unusual irritability
• Unusual limpness
• Extreme stiffness
• Feeding problems
• Lethargy (hard to wake up)
• Seizures
• Vomiting
• Fever

If you're at the hospital and notice your newborn having any of these symptoms, get help immediately.

Can my baby get a group B strep infection later?

Yes. It's possible for a baby to develop a group B strep infection after the first week, whether or not you tested positive. This usually happens within three months and is called late-onset GBS disease. In the United States, late-onset GBS disease in babies occurs slightly more often than early-onset GBS disease.

Late-onset GBS can cause the same problems as early-onset GBS and affects 3 out of every 10,000 babies. As with early-onset GBS, babies born prematurely are at higher risk. Meningitis is more common with late-onset disease.

Signs that you should call your baby's healthcare provider include:

• Unusual irritability
• Unusual limpness
• Extreme stiffness
• Feeding problems
• Lethargy (hard to wake up)
• Seizures
• Vomiting
• Fever

Is there any way to prevent late-onset GBS disease?

Receiving antibiotics during labor won't prevent late-onset GBS disease. Only half of babies who get late-onset GBS have mothers who are group B strep carriers, and nobody knows how the others get infected with the bacteria, so prevention is difficult.