Group B Strep. GBS.
Chances are high that if you're pregnant, or have been since 1993, you've heard SOMEONE refer to Group B Strep. You were probably even tested for it. So what IS it and should you treat for it if you have it?
Group B Streptococcus (GBS) is a bacteria that lives in our intestines and can be present at any given time in the rectum, vagina, and/or urethra. In the United States, women are generally tested for it using a swab of the rectum and vagina around 36 weeks. If the bacteria happens to be present at the time of the swab, you will test positive for it. 1 in 4 pregnant women will test positive.
Since 1993, the American College of Obstetrics and Gynecologists (ACOG), the American Academy of Pediatrics (AAP), and the Center for Disease Control (CDC), have recommended that all pregnant women be screened for GBS and if tested positive, are treated with IV antibiotics in labor. This is done in an attempt to prevent newborns who may become colonized with GBS during labor and delivery from contracting a serious infection known as early-onset GBS infection, which can cause meningitis, pneumonia, and sepsis.
It is important to note that colonization of GBS is NOT the same as infection. About 50% of newborns born to GBS positive women who DO NOT receive antibiotics in labor will become colonized with it. Most will not show any symptoms and stay perfectly healthy. However, 1-2% will develop a life-threatening infection.
When antibiotics are given in labor, that risk drops 80%, so from 1-2% to 0.2-0.4%. Another way to put it is that if you test positive for GBS and receive antibiotics in labor, you have a 1 in 4,000 chance of your baby developing a GBS infection. If you do not receive antibiotics in labor, that chance becomes 1 in 200. Of these newborns that DO develop an early-onset GBS infection, 2-3% of these infections will result in death.
While about 60% of newborns who develop early-onset GBS infections will do so for no reason other than their mother had an active colonization, there are some things that increase the risk of infection.
The most common risk factors include:
Being born before preterm (before 37 weeks)
An extended period between water breaking and birth (>12 hours)
A high maternal temperature in labor (>99.5*F)
Additional factors that increase the risk include:
Being African American
Water breaking before going into labor
Infection of the uterus (chorioamnionitis)
Intrauterine monitoring during labor
History of having a newborn with an early-onset GBS infection
Having GBS found in urine during pregnancy
In order for antibiotics to be most effective for GBS, the CDC recommends that they be administered every 4 hours in labor and at least 4 hours prior to birth. This means that if you get antibiotics in labor but deliver prior to 4 hours since the first dose, they may not have had time to take effect in the newborns system and risk of infection could still be as high as someone who didn't receive any antibiotics at all.
The antibiotic used to prevent infection is penicillin, as it can easily cross the placenta. For women who are allergic to penicillin, the alternatives are Cefazolin, clindaymycin, or vancomycin.
The main concerns that many have in prophylactically treating for GBS infections are:
Adverse reactions to the antibiotics (in mom OR baby)
Increase in maternal and newborn yeast infections
Unknown effects on newborn's gut microbiome
Numerous women choose to attempt to prevent GBS colonization in the first place by using alternative natural methods during their pregnancy, such as regular and consistent use of garlic supplements, colloidal silver, and probiotics. There is little to no scientific evidence available to attest to both the safety and effectiveness of these remedies and we recommend that you speak with your provider before beginning any of them. Some women choose to skip GBS testing altogether in their pregnancy. Others will test for GBS and even with a positive result, still refuse antibiotics in labor but be on higher lookout for any signs or symptoms of infection in their newborn.
Ultimately, whether you are treated for GBS with antibiotics in labor or not is completely up to you and you DO have the right to refuse any treatment, regardless of provider or hospital "policy." We just recommend that you do your research, talk things through with your partner (including how you would feel about and handle it should your newborn end up with an early-onset GBS infection), and speak with your provider regarding your choices.
For more information regarding GBS, visit the CDC website, Evidence Based Birth, and even the National Health Service (UK's version of the CDC) website.