Monday, September 4, 2017

Looking at Group B Strep Testing

Evidenced Based Birth's update to their Beta Strep information gave me LOTS to think about...


Most mothers in the US are tested for GBS during the final weeks of pregnancy. Like every test or procedure there is lots to learn before you decide to say yes or no thank you to your care provider. An excellent place to gather info is the Evidenced Based Birth site. I encourage you to read the section about Group B Strep carefully. Ask your doctor or midwife informed questions based on what you have read. Craft a plan of action. Be prepared to change it if your circumstances change. Don't forget to be proactive about repopulating your gut flora immediately after birth and include baby too. Understanding Beta Strep; risks, tests, treatment Many women have Beta Strep in the vagina. Many of those women if not given antibiotics will colonize their babies during the birth process. This means Beta Strep will be found on the skin and mucosa of the infant. BUT this doesn't mean the baby will necessarily become sick. Being colonized doesn't always equate with sickness. Most babies who actually become ill with Beta Strep have been colonized in utero before birth and show signs of illness within hours of birth. Most babies who die from Beta Strep were born preterm. Universal GBS screening followed up with antibiotics in labor for all women who tested positive has cut the number of neonatal Beta Strep deaths in half in the US. Very few babies actually die from Beta Strep but to cut this rate in half is significant. Whether this is from the Universal screening OR from the push to use antibiotics in labor is debatable. You'll see why I say this later. Most babies who become ill with Beta Strep need NICU care for days or weeks; disrupting the bonding and breastfeeding process. This is a big strain on the family emotionally, physically and financially. This article doesn't have stats on if we have lessened our NICU admissions with universal screening and antibiotics in labor. It may be difficult to know because many babies are taken to the NICU because they MAY have Beta Strep. They are started on a course of IV antibiotics just in case. We can only know if they actually have it after a culture has grown which takes a number of days. So some babies are receiving NICU care and antibiotics who need it, and some are receiving it who don't. To Screen or Not to Screen? Different countries use different approaches. U.S. uses Universal screening followed up with insisting on Penicillin during labor for all GBS positive women. Great Britain uses Risk Based screening. So only women with certain risk factors are screened. I don't know how insistent they are about antibiotics but the language in their National Institute of Health and Social Care Excellence (NICE) documents use various levels of insistence depending on situation. They range from offered, to considered, to prescribed. Here is their current thinking on why they choose Risk Based screening: Dr Anne Mackie, Director of Programmes for the UK National Screening Committee, said: "At the moment there is no test that can distinguish between women whose babies would be affected by GBS at birth and those who would not. This means that screening for GBS in pregnancy would lead to many thousands of women receiving antibiotics in labour when there is no benefit for them or their babies and the harms this may cause are unknown." Dr. Mackie ties this decision to the microbiome which we'll discuss more in a minute. "The results showed that the infant microbiome was influenced by antibiotic exposure during labor, birth route (Cesarean or vaginal birth), and breastfeeding." These are the unknown harms she is referring too in the first quote. New Zealand uses Risk Based Treatment rather than screen. Like the UK they have a set of risk factors that they use but rather than screen they simply begin antibiotic treatment in labor. They also seem to move from suggestion to insistence depending on risk factors present. They have a flow chart to show when to move women into different management. It appears that using THIS approach they too have cut their GBS mortality rate in half! So which approach has the lowest baby mortality rate associated with it? New Zealand! Comparing GBS Baby Mortality Rates UK: .38 per 1000 babies born US: .24 per 1000 babies born NZ: .2 per 1000 babies born Does this mean a risk based treatment approach is best? Not necessarily. Being associated doesn't prove a causal link. There may be more going on here; genetic factors, other labor management factors, or immediate newborn care factors, even a less virulent strain of GBS is possible. Other possibilities? Dietary changes and other cultural changes that could effect the bacteria present in the birth canal before or during labor. Bottom line? No one knows for sure yet. The Good and Bad of Antibiotics How does IV Penicillin in labor work? From the EBB link: "Penicillin rapidly crosses the placenta into the fetal circulation (at non-toxic levels) and can prevent GBS from growing in the fetus or newborn." Pretty straight forward. They are dosing not only you and killing your Beta Strep bacteria but also any already in your baby's system. Of course they are also killing all your good gut flora and your baby's too. This may be why there has been a rise in the rate of preterm babies dying from E. Coli sepsis. So to actually decide if we have done a good thing giving antibiotics in labor we would need to add baby mortality from Beta Strep to baby mortality from E. Coli and compare that rate to before we began using labor antibiotics. Didn't find those statistics in my research and it isn't in this link. Stumbled onto this possible connection with E.Coli rise in a different research paper. Back to Dr. Mackie of the UK's concern about causing harm in some unknown way. Here is what Evidenced Based Birth says, "Research is needed to determine if there are any long-term effects associated with the temporary reduction in beneficial bacteria". Understanding the human microbiome is a rapidly evolving science. So far we know that some bacteria seem to turn on or turn off various genetic switches. Having evolved over thousands of years in a symbiotic relationship with the bacteria in and on our bodies we are linked right down to our DNA or gene expression. We are just beginning to understand this. It will be some time before we understand all of the impacts of this relationship with our body's flora. We know different women carry different balances of various microbes. What the perfect balance is? No one has a clue yet. But good or bad, passing down your microbiota is part of your genetic inheritance to your children. We know there are properties in breastmilk designed to feed certain bacteria and resist the growth of other bacteria. So the body knows what balance is best. This is why breastfeeding can help mitigate the effects of the labor antibiotics. Evidenced Based Birth says, "Research is needed to determine if giving probiotics to mothers and/or newborns can help lessen or reverse the impact of IV antibiotics on the infant’s microbiome." Well first we need to determine what all the impacts are. We know mother and baby have double the risk of developing thrush if she has antibiotics. Thrush impacts breastfeeding big time. Taking probiotics and breastfeeding appear over time to bring back the gut flora but it can take anywhere from a few weeks to a year. When do microbes effect gene expression? We don't know. Immediately after birth? During the first days or weeks? We don't know. Does it happen while in utero or in labor? We don't know yet. But there is bound to be a critical period for this. We just haven't a clue when it is because we don't even know yet how they are doing it. Can You Lessen Your Risk? Is there another way to lessen your baby's risk of GBS? EBB shows a study that says, "probiotics (lactobacilli) may lessen your chances of being colonized with GBS." Wait a MINUTE! So perhaps we need to talk to moms about their DIET and how to lessen their potential Beta Strep load. In other words PROACTIVELY support women in bringing their bad microbe load of ALL types down as a way of circumventing the need for antibiotics by teaching them how to bring their body's flora into better birthing balance. The study EBB refers to shows that even putting probiotics onto panty liners can be helpful. What if moms did that starting after their first prenatal visit, and took probiotic capsules and ate and drank probiotic foods? What if we studied the difference between that group of women and the women being universally screened and automatically given Penicillin? What would we find at their 36 week screen? Would we prevent preterm births? Would we be able to maintain the same mortality rate from GBS? Or perhaps even do better? What would happen to the E. Coli death rate? I have no answers to these questions but they are IMPORTANT questions. Final Thoughts Please do not think I am telling you to blow off your GBS test. Please read all the research EBB presents. Consider carefully all the known risks, your current risk level (which can change), and the possibility of unknown risks. Please DO NOT use probiotics and dietary changes as a way to get a negative GBS test and then revert to old eating habits and discontinuing probiotics. Definitely read the article and talk carefully to your care provider.