The gentlebirth.org website is provided courtesy of
Ronnie Falcao, LM MS, a homebirth midwife in Mountain View, CA


Archival Pages about GBS Protocols

Easy Steps to a Safer Pregnancy - View e-book or Download PDF - FREE!
An interactive resource for moms on easy steps they can take to reduce exposure to chemical toxins during pregnancy.

Other excellent resources about avoiding toxins during pregnancy

These are easy to read and understand and are beautifully presented.

These were mostly collected around 1996/1997, around the time the CDC/ACOG/AAP Consensus Guidelines were released.
They are out of date and are preserved here for historical/archival purposes only.
Please do not rely on these protocols are being current.

GBS Protocol from Department of Family Medicine, University of Iowa's Protocols Pages

Here's my take on GBS. I give my moms the literature and let them decide. I tell them that one or two babies out of of 100 will become sick with moms positive with GBS. Then I tell them that I recommend they take antibiotics AFTER 18 hours with ROM and no labor and they do this with a 2000mg bolus po and then 500 q6. I feel that in letting the parents decide if they want to test and what they want to do about it, I am not making choices for them. I do not underestimate the serious nature of GBS but I try and put it in perspective.

I work at a hospital here in Australia. We treat all Gr B Strep positives with IV antibiotics during labour - we also treat every woman who was previously positive (i.e. last pregnancy, despite being negative this time) as well... You know the saying 'Once a ...., always a.....' But we don't routinely culture anyone - we only pick up the ones we pick up because they've been swabbed for a symptomatic reason. Prolonged rupt membranes and pre-term deliveries are also treated with IV antibiotics.

Now this is all for the benefit of the baby isn't it - so, we take a gastric aspirate and a urinary latex from the baby as soon after birth as possible and do 3rd hrly obs on the baby. If the aspirate or latex comes back positive we still don't treat the baby unless the baby is symptomatic i.e. hyperthermic, hypothermic, resp distress, etc. You might well ask why we bother with the tests if we don't act on them - and I often do. Nobody to date has mentioned observing the baby - how do you manage that in the home birth situation. I know it sounds obvious - get the parents to observe, but is that really good enough when it comes to Gr B strep and the potential it has?

SO in essence, you are only treating women with symptoms and women with risk factors! This is ACOG's protocol (unless they've changed it).

You are actually treating only those babies with symptoms. I agree with your wondering 'why" the testing if no treatment is given unless symptomatic. (though I guess it could make speed diagnosis if a baby does become ill).

We are only dealing with term births. women with fever in labor or other symptoms would be transfered for treatment with antibiotics etc.

We observe the baby for several hours after birth, and leave careful instructions with the parents. We keep in touch by phone and usually do several visits over the next few days.

So what we end up with is "mom has no symptoms, and baby has no symptoms".. That's the way we like it [VBG]!

I am not culturing routinely, I feel way behind the times on this one. I am doing a waiver, but I have been doing so few clients this past year that I admit to putting this issue on the back burner. I really feel like I need to develop a protocol and stick with it. I am not prepared to offer IV antibiotics in labor although a nearby midwife offered to train me and said it wouldn't be hard to get a pediatrician to give me the prescription. I just have a REAL hard time with needles. I do venipuncture, heelsticks, fingersticks and IM injections (when I have to), but I HATE it. I can't imagine doing an IV, but I know I could learn. What I did with the last two people I cultured was ask them to take acidophilus/bifidus for about two weeks before I did the culture at 36 weeks. If they came up positive (which they didn't), we were going to hit with echinacea, chlorophyll and more acidophilus/bifidus, Vitamin C and try to get a negative culture at 38 weeks. Then, if we didn't we were going to decide about antibiotics at that point. Well, we didn't have to.

My question is this: Is this kind of think OK in your collective opinions? Am I manipulating the test for a false negative? (I doubt it but - "there are no stupid questions" right?....) If there were risk factors (previous infection, PROM, etc.) I would definitely have to do some other kind of CYA thing, but so far haven't faced that as I have had mostly primips and repeat clients that I have done all their births for in my practice.

I don't know ... Can anyone really be sure that acidophilus and echinacea and vit C are effective at reducing strep colonisation in the genital area? It doesn't sound like it could hurt anything of course.

My recommendation: just stick with the ACOG protocols! Unless they've recently changed they say NO universal screening, and DO treat risk factors in labor. ACOG and CDC disagree on universal screening -- I figure ACOG knows better on "this" issue, so why screen? Especially why screen if you do not intend to treat?

I like the summary of the two competing protocols. "Screen all and treat all positives. -- OR -- Don't screen and treat those with risk factors" . It still makes good sense to me to adopt one or the other -- and not to mix them up into a third and unapproved protocol (testing ,but not treating the positives unless risk factors develop). Why test if we don't intend to treat?

If you are doing homebirth then you probably are already referring for these risk factors anyway - - - preterm birth, and fever in labor (signs/symptoms of amnionitis). The only problem comes with PROM beyond 18 hours... If you followed ACOG protocols you would either need to begin antibiotics if mom is strep positive or unknown status; or else you would have to get a negative strep test to avoid antibiotics. Or, give really extensive informed consent if your client wishes to refuse antibiotics if she goes beyond 18 hours ROM without a culture -- or with a positive culture.

[from ob-gyn-l]

We're having a little difficulty with our GBS protocol here. We decided to NOT culture our patients at 36 weeks, and not treat in labor unless at risk (h/o, PTL, prolonged ROM)per the ACOG and CDC protocol. Our pediatrician, therefore, has decided to keep all our neonates for 48 hour observation. In reviewing this I found a relevant site. Carol Baker is apparently one of the experts on neonatal GBS infections, and cites the AAP recommending this 48 hour observation unless two doses of PCN have been given before delivery. Most of our Moms can go home before 48 hours, but none will leave their babies (duh!)

I find this protocol hard to understand, expensive and wasteful of resources and inconvenient. Anyone have a similar problem, or a way to get around this?

Sounds punitive to me. Our neonatologists recognize that we are trying to deal with a rare event in a rational manner, and only watch those with risk factors - like they always did before.

Yes, we have the same problem -- and the same response from our pediatricians. Until CDC or ACOG come out with a more sensible protocol, I'm afraid we are stuck with the inconvenience and expense of culturing everyone at 35-36 wks.

We also follow the ACOG recommendations and haven't had a problem with our peds department. The kids go home with the moms if they're OK...plain, simple and less expensive.

We do the same thing. No problem with the moms. Around here (France) we keep the moms 4 to 5 days post delivery

You might want to check out the Parkland protocol. They don't culture and don't treat in labor. They just give Penicillin G to every baby after delivery. They claim a cost of $0.17 per delivery and have reduced their GBBS infection rate to one-half what it was when they cultured and followed the AAP protocol. It also treats the 5% of infants from Mothers with negative cultures who are colonized.

Ref. Obstet Gynecol 1996;87:692-698 Siegel et.al.

I recently spoke at the AWHONN District II Intrapartum Practice Summit on Long Island and heard Dr. Ian Holzman of Mount Sinai Medical Center, NY, NY, speak on what has been called "the Parkland protocol". He told us that Mount Sinai instituted the use of PCN in neonates in the early 50's as eye prophylaxis. They have looked back at all deliveries (I think more that 50K) since then and have an almost absent incidence of neonatal GBS with few, if any, complications. He also told us how Parkland began using this protocol, decreased the incidence of GBS in their population, stopped using the PCN, and had an increase in incidence. This caused Parkland to again use the PCN protocol. He has published an article, but I do not have the reference.

I wonder what the newborn's risk for subsequent penicillin allergy might be? I'm assuming there were no outright penicillin anaphylactic responses. I may need to return to Pediatric immunology 101, but does that ever happen?

newborns do not have a mature immune system. they will not develop an antibody response and will not have an antigen antibody reaction.

Unless they carry maternal antibody to the antigen (penicillin). I'm not certain how significant this type of reaction would be as existing IgG would be rapidly consumed and not replaced.

I've heard of the Parkland protocol, and it sounds attractive. My only concern is my reluctance to give even one unnecessary antibiotic in these days of increasingly drug-resistant pathogens. This was standard procedure at one of my hospitals for a very long time but I believe was stopped because it's effectiveness was questioned and intrapartum treatment was better proven. Perhaps the pendulum is starting to swing again. Except for the resistance issue my understanding is that the best approach is to treat everyone in labor (I can dig out the reference if necessary).

I would agree that treating all newborns with Pcn seems interesting but I'd like to know what the risks are. Also do they have any data that they're outcome is improved other than theoretical considerations. Surely a place like Parkland would publish a protocol like that if they've been at it long enough.

We're thinking about getting away from the ACOG protocol and screening everyone at 35-36 weeks and treating positives in labor only. This would pick up the percentage that you miss with the ACOG protocol. We wouldn't screen high risk patients since they'd get treated regardless of test results. This was recommended at a recent conference. What do people think?

We do the R/V culture on specific GBBS media at 36 weeks (even if history of GBBS or planned C/S). Treat with Amp in labor or Clindamycin as G Klien wrote. I'm not certain why Amp was chosen rather than Pen - I wasn't present at the discussions...

So what are we doing giving Ampicillin in labor to the mother and fetus? When you realize that 20% of all pregnant women have GBBS and will receive Ampicillin in labor and that 5% of women with negative cultures will carry GBBS and won't receive Ampicillin in labor. Also that without treatment, the incidence of early onset GBBS disease in the fetus is 1/1000 deliveries. And that treatment only reduces it to 1/2000 deliveries.

Putting the above together, you realize that we will be treating 400 mothers and 400 babies to prevent 1 case of early onset GBBS infection. In other words we needlessly treat 400 women and 399 fetuses to save 1 fetus.

This is, in fact, THE PROBLEM. Is there enough risk associated with "unnecessary" antibiotics in 400 patients to outweigh the death of one baby? Someone already mentioned increased antibiotic resistance. Also there's allergic reactions in some mothers.

The bottom line is, what do you balance that one baby's death with? if it's, for the sake of argument, one mother's death by anaphylaxis and one neonates death from a resistant bug, then that's one thing. On the other hand, if you're balancing a baby's death with 400 doses of a cheap antibiotic, then that's NOT reasonable. Of course, the answer is vague and lies somewhere in between.

Considering the one baby could end up dead, and the other women and babies appear to have negligible risk, the numbers sound pretty good to me.

Why not just culture everyone at the first prenatal visit when you've already got a speculum in and you are doing other cultures? Then if hear a peep out of the 26 weeker with a little cramping, you treat her. We just hate to wait til the last minute to consider someone at high risk when the patient might have been identified, counseled and/or treated earlier.

It is not cost effective. And if you treat during the pregnancy you got a GBS back in 22% of the cases.

The culture results at the first visit have little to do with the presence or absence of GBBS at delivery. Also one does not do GBBS cultures with a speculum. The cultures are taken from the vaginal introitus and the anal orifice. Both sites are necessary. Only treatment during labor or treatment of the newborn has been shown to have any effect. There are 5% of women with negative cultures at 36 weeks whose newborns are colonized with GBBS anyway. Unless we can wipe GBBS out of the environment or discover what makes one baby out of a thousand susceptible to this organism, we won't make much headway.

I agree. We, and many of our colleagues at one major institution, use the ACOG protocol. We have been very successful with GBS in that we have reduced problems in the nursery without unnecessary treatment of the majority of patients. Every infant is precious and we are not taking any for granted. A Perinatologist on Long Island (forgive me, forgot the guy's name) stated just before the ACOG protocol came out that the CDC or Peds protocols might cost more lives than they save (in the long run) due to resistant strains in treating patients unnecessarily for positive cultures at 35-6 weeks or earlier who were no longer positive, leading to a treatment for somewhere between 50-75% of all patients between culture results and high risk criteria. Scares the beegeebers out of me.

My understanding is that about 30% of women in the childbearing years have GBS at some time, but that our immune systems normally handle it, so it appears to come and go. The critical issue is whether the woman is colonized at the time of delivery, esp. with risk factors such as prematurity or prolonged rupture of membranes. Neither a positive nor a negative test prenatally is predictive of GBS status at the time of delivery. If she is only colonized intrauterinely, we won't know unless she ruptures. But even if she is colonized vaginally or rectally, the rapid strep cultures available when she presents in labor lack sensitivity and specificity, and the more accurate testing requires longer than most labors.

I understand the ACOG protocol of testing late in pregnancy, under the theory that the body will not be able to "cure" itself in time for delivery. Has that proposition been tested? How much correlation is there between tests done at 36 wks versus at delivery of otherwise healthy women?

No one wants a septic baby, least of all me. But I also do not like to give unnecessary antibiotics, and without intrapartum symptoms or other risk factors, and with no confirmation of current infection, I'm reluctant to treat. It seems it would make at least as much sense to treat at ~36weeks when the infection is discovered as to wait to prophylax during labor.

After three neonatal deaths by E.coli resistant to Ampicillin secondary to unnecessary treatment of Moms in labor, even our pediatricians during my residency requested we only treat those with positive risk factors. No, I don't agree with treating everybody, nor anybody without risk factors.

These should be reported. The only LITERATURE citations of this were a couple (or three?) cases from Denver a few years ago. If anyone has any other references, then I stand corrected. But this type of thing NEEDS to be put in print, so the argument can be made adequately.

The current recommendation for GBS treatment for the non-pen allergic patient is Aqueous pen G, 5 million initial with 2.5 million Q6 and not Ampicillin for the very issue of resistance. I just delivered a patient with PROM at 22.5 weeks at 30.5 wks gestation with acute chorio, The organism selected out after several weeks of Pen VeeK oral Rx was a Strep viridans sensitive only to vanc. The induction of resistance is a real issue.

CDC recommends aqueous Pen., because of a growing concern for resistant strains of GBS.

Based on the CDC recs from a year ago, this is my interpretation.. If a patient has a negative culture in the first trimester and has a GBS affected baby delivered at term, someone might be willing to testify that standard of care was violated.

In the case of a 26 weeker, I would initiate treatment on admission. If she was still pregnant 48 hrs later when the culture came back negative, I would stop it..

Anyone disagree?

No I would not disagree with that. In fact, it seems that the treatment of threatened preterm labor and of PROM both now include IV Ampicillin until the GBBS "CULTURE" returns negative in 48 hours. You can not rely on a negative "quick" test for GBBS. If it is positive it is accurate and the patient has a high colony count. If negative the patient may still have a low colony count which is still significant enough to cause the disease.

Does anyone know any study on the prophylactic use of routine perineum disinfection after any bowel movement with chlorhexidine for prevention of vaginal contamination by colonic flora, as a mean of reducing the number of carriers by the time of labor? It was an idea of my director and I'm just wandering if someone else had the same idea!

If they are positive early in pregnancy, shouldn't you assume a carrier state, and act accordingly? I don't see the purpose of repeating the culture at 36 weeks.

Well, we were clearly caught in a time warp here; assuming that occasionally oral antibiotic therapy was effective in eradicating GBS. And so if the culture was negative at 36 weeks, we did not use antibiotics in labor. We did however if prolonged ROM, fever, or anything suspicious. We did have one fetal death, as I mentioned, in a first twin, though I don't think the ACOG protocol or the CDC protocol would have saved that child, God bless her little soul

Now that we've absorbed the CDC guidelines, they say only to treat GBS with oral antibiotics if it is cultured from the urine. (They also say that once in awhile a physicians overwhelming preference to treat + vaginal cultures may be considered OK.) But in general they would prefer no oral antibiotic be given antenatally to treat GBS unless it's in the urine.

I liked the old protocols, screen no one, but Rx (1 gram ampicillin IM) anyone ROM over 12 hours, anyone <36 wks, or with hx of a Strep B baby. Developing a Strep B protocol I can live a big dilemma. We tell parents what the medical standard is now, and let them decide. However, most of my parents look to me to interpret standards and make recommendations (why can they all be totally educated and decisive?).

My current protocols are: culture at intake, (we already culturing for everything else anyway) if she test positive, we ignore it until 32 weeks, put her on echinicea & vitamin C for a month, reculture her at 36 weeks. If still positive, we give her the option of antibiotics IM in labor if ROM is over 12 hours. We don't do rectal cultures (no good reason, I just hate them).

This is a compromise, not up to ACOG or AAP standards, but since I am not required to follow any protocol but my own, it works for now.

Dec 1994 guidelines from the Center for Disease Control for Group B Strep.(Federal Register/Vol.59. No 240/ Dec 15, 1994:

  1. Screen all pregnant women at 26-28 weeks for GBS colonization.
  2. Use cultures that maximize likelihood of GBS recovery.
  3. Oral microbials for women who are colonized is not effective in eliminating the carrying or preventing neonatal disease.
  4. Give antibiotics (in labor( to women with a history of previously giving birth to an infant with early onset GBS.
  5. Give antibiotics to pregnant women who are identified as carriers who meet at least one of the following criteria: a)Intrapartum fever (not from some other factor) b) onset of labor or PROM before 37 weeks or c) rupture of membranes longer than 12 hours (this used to be 18 hours)
  6. Antibiotics recommended: IV Penicillin G (5 million units every 6 hours) or Ampicillin (2 GMS) initially followed by 1 Gram every 4-6 hours) until delivery. Clindamycin or Erythromycin may be used for women that are Penicillin Allergic, though not considered as effective.
  7. Treat women found to be + with GBS with a symptomatic/asymptomatic GBS bacteriuria during pregnancy at the time of pregnancy. Intrapartum antibiotics should be considered for these women also. The Natural Choice Birth Center
Using this protocol, difference in risk is half:
3 in 1000 develop if untreated
1 1/2 in 1000 develop even if treated in labor

There is also an address at the end of the article for those wanting more information on GBS. Contact Group B Strep Association, P.O. Box 16515 Chapel Hill, NC 27516.

Updated GBS Bulletin from ACOG

May 1996 CDC bulletin gave 2 choices for management of Group B Strep surveillance. One for prenatal cultures and risk factors and one without the cultures. Both are felt to be acceptable. Also included was recommended management of the infant at risk.

The ACOG doesn't go along with the CDC and ACP recommendation of universal screening for GBS because of cost concerns. Screening is really expensive, and identifies a lot of people who will never have any problem or reason to be treated. Thus they recommend only screening high risk women (in preterm labor or with premature ROM). They do recommend a screening urine culture for everyone, and treatment if positive.

Sadly, I don't think that it will resolve anything. If I am not wrong, it will recommend universal screening--for which there is no evidence of benefit. A consensus report is about consensus not about science necessarily. It is possible to be in agreement based on misinformation or misinterpretation--or based on an emotional response to ambiguous information. The reality is that the correct course is not clear, and it will not be made more clear by choosing a path that is not evidence based no matter how seductive. We in Canada will not follow such a recommendation.

I give women a choice as to whether they want a routine culture at 36-37 wks or be treated on only a risk basis. Only one so far has chosen a routine culture (which, thank goodness, was negative, so we didn't have to do anything about it).

I use the CDC info sheet that I got off their web site and have the parents read it, the select the course they choose to take. Again, I can educate, but don't think it's appropriate to make their decisions for them. I'm working on an informed consent form for them sign, esp. if refuses prenatal testing and/or treating if risk exists in labor (such as PROM more than 18 hours, but no sign of infection).

I don't have a cutoff on the basis of PROM alone, and will discuss options with clients (risk of infection, risk on intervention, etc) - let them make the choices. I'm comfortable at home unless mom or baby shows sign of infection (fever, tachy, etc), then parents don't get a choice anymore - we go to the hospital.

I think immunity may be better in homebirthers who are healthy and well-nourished, but don't believe we are protected completely.

The CDC has recently come out with protocols for prevention of GBS morbidity and mortality.. The entire document, which is well worth reading, can be found at their site, under publications (Morbidity and Mortality Weekly Report, May 31, 1996.) You need Adobe Acrobat to down load it, but you should be able to read it without Adobe Acrobat. (http: to Publications go to MMWR then select 5.31.96)

There are basically 2 arms, or protocols....one involves testing everyone in late third trimester (>35-36 weeks) and treating all positive cultures in labor. The other suggested arm is treating only risk factors in labor...ie prematurity, fever, ROM > 18 hours, +GBS UTI, previous child with sepsis. The CDC is quite specific....don't test for GBS early in pregnancy, and don't treat positive cultures prior to labor....it just doesn't do any good. Neither arm has been shown to be superior. No protocol will alleviate all perinatal GBS. The important thing is to pick a protocol, inform your clients of it, and stick to it. So, to answer your questions, here's how we do it...

We never culture in pregnancy (unless they are in preterm labor) and never treat positive cultures which might be found for other reasons (except if GBS UTI). We take the risk factor approach, and treat only women with risk factors in labor. The state has absolutely no control or input into our protocols. We do not induce after 18 hours, just let women with PROM wait til onset of labor (assuming that the culture which we take upon ROM is negative, and they have no history of GBS).

Our basic policy with respect to Group B Strep screening is to routinely test all patients that present with premature ROM, or ROM with no onset of labor at the time of admission. Of course patients with a prior history of the bug are routinely screened, and any patient with prolonged ROM that may have tested negative on the initial screen that suddenly becomes symptomatic of a possible infection are treated in labor with IV abx.... We do not routinely screen all patients.

About new CDC guidelines:

[from ob-gyn-l]

Very controversial stuff. Nobody knows the ideal answer. There are three different protocols. The peds, The CDC, and the ACOG.

I follow the peds because they deal with the aftermath, the 6000 babies a year that die from group B beta-hemolytic strep.

So I think everyone should be screened at 36 weeks. Then treated in labor if they are positive. They should also be treated for prolonged ROM if strep status is unknown. There are other reasons to screen and treat of course.

The strep carrier status is not a disease. It is normal, and present in one third of individuals. It is not 'curable' in the sense of eliminating it from the colon, etc, just as the colon cannot be sterilized.

But the babies need to be protected from it. The studies show that effective prevention is IV antibiotics in labor. The mechanisms of infection and prevention are unknown to me, and probably to everybody else. But presumably the baby breathes it in vaginal fluids during delivery, or it just goes in through the skin.

This protocol will save about 5000 babies a year, at a cost of about 1,000,000 doses of AB'x. 5000 babies is 1 per hospital per year in the US.

Everybody is concerned about resistance development, anaphylaxis, minor allergic reactions, etc. We just don't know.

In my practice, only about 1 in 20 women will decline screening. And I always enjoy this, because I know they are making a fully informed decision.

Do you get the feeling that by getting a negative culture you are out of danger? Seems to me that this prophylactic testing is just false and dangerous reassurance.

Just over this past summer I know of 2 separate cases of term babies with neg 35-37 week cultures without risk factors in labor who developed full blown Group B strep sepsis at our hospital after delivery. One is on echmo the other died. This tells me two things. 1. This protocol is far from perfect 2. Anyone not following the test and treat protocol is hanging by an extremely thin thread if they have a GBS baby. Even though it may not have been preventable even with the protocol as in 1. above, you can bet you'll be held to that standard.

The irony in this is that the cost analysis done by the CDC the "UNTHINKABLE" was the most cost effective, i.e. treat all women intrapartum with penn G.

I work in a collaborative OB/CNM practice with the most aggressive approach to GBS prophylaxis I've ever heard of--kind of a hybrid of the ACOG recommendations. No outcome data are available since we do only 450-500 deliveries/year and have evolved the approach over 6 years. Our population colonization rate is between 20-25%.

We culture all women at 36 weeks or anytime in pregnancy if they bleed or have preterm cervical change with contractions. We consider any history of positive vaginal or urine culture for GBS at any time in life to be colonized at time of labor, also anyone with history of neonatal sepsis in other infant regardless of culture result. We also regard women with negative cultures but risk factors at time of labor as colonized. We treat all positive antepartum urine cultures with ampicillin, and use Ampicillin for intrapartum prophylaxis. Status of membranes does not affect prophylaxis of colonized women, and c/s without labor also merits prophylaxis in these, at least 1 hour prior to delivery. We are aggressive as well in our efforts to identify and treat bacterial vaginosis in pregnancy. We practice in a high-risk environment for litigation.

I maintain that this is "dangerous talk" - we are allowing the lawyers to convince us that we are no longer scientists! These numbers (86% and 68%) are NOT comparable since they came from different populations and different studies. I know that Ken knows this - but please let us not allow ourselves to bypass thoughtful science in what will surely be a vain attempt to "out-lawyer" (not out-smart) the lawyers. Now I'll get down from my soapbox.

I agree. You might just as well wait for the first adverse event from the ampicillin (e.g., an anaphylactic reaction, or a resistant GNR in the nursery, selected by the ampicillin) and then worry that the lawyer will come after you for doing TOO MUCH "prophylaxing," when a less invasive (numerically speaking) regimen could have been used.

Why are we treating at all? I thought the idea was to prophylax intrapartally to prevent infection of the neonate. GBBS since it resides in the vagina or 25% of all pregnant women is by definition; Normal Vaginal Flora. It has been shown that after treatment, it will return in a large number of women within a few days of completion of the course of therapy. Perhaps it gets reinoculated by the significant other ????? If we are going to treat 25% of pregnant women because they have a positive culture then (carrying thing to the next conclusion) we should treat all of their sexual partners... That ought to really increase the cost of preventing 50% of cases of a problem that only affect 1 in a 1000 if you do nothing.. Makes sense to me.(Irony)

Have anybody thought the cost of resistant to Penicillin GBS as a consequence of systematic treating all women or all newborns?

The point I was trying to make is that there is NO data that shows that one strategy is better than the other - there is no reason to think that you will save more babies or be more efficient with one over the other. The only way to do this IN THE REAL WORLD is a head to head RCT!

Our OB/GYN department agreed to use the alternate protocol, i.e. tx only of those patients with identifiable high risk factors, rather than the culture method. We did some local evaluation that suggested we would have to treat 27% of all our patients with prenatal care if we had chosen the culture method. Only 14% will require antibiotics with the alternate method, and, of course, practically all no-prenatal-care patients would require them with either protocol.

The 2 "options" for management of Group B strep screening are well explained in the CDC report of about June, 1996 (they have a website--use a search engine under "CDC" to find) or in the ACOG report of June, 1996 (I bet you can get this from www.acog.net, but I'm not sure).

Briefly, the options are:

1. Screening all at 35 to 37 weeks, as you mentioned. All positives are treated in labor, regardless of risk (see below).

2. Not screening, but culturing and treating women in high risk situations for neonatal disease, ie ROM more than 18 hours, prematurity, or those whose previous infants have gotten ill. The family practice docs need to read these reports and do one or the other to be in line with the standard.

Personally, people much smarter than I have evaluated multiple ways to handle this, and the big boys at ACOG/CDC/Am Assoc Peds have come up with these 2 choices. While it is up to us, as clinicians, to make decisions, whenever I enter into lengthy discussions with pregnant patients about the 2 options, they invariably want to test. Of course, they do not understand, as we do, the concerns about antibiotic exposure, resistance, cost, etc--but the "big boys" have already thunk on this one, so I'm culturing all of them.

All the Obs in our town are following the ACOG/CDC guidelines. I suspect that whether or not the statisticians are correct in their interpretation of the data, one would be hard pressed to defend oneself medically or legally if a baby developed GBS and the ACOG guidelines were not followed.

Our practice is to follow the "treat for risk factors" option in the guidelines.

Let me ask -- were the Mom's who were cultured at 35-7 weeks and tested negative for GBS, only to go on and deliver very ill GBS septic newborns; cultured with selective media, with appropriate transport media, and with rectal source included? The yield for GBS drops when Todd-Hewitt (naldixic acid/gent/sheep blood) is deferred. (False neg rate close to 50%). The guidelines specify 'selective media', and even suggest transport policy (delayed inoculation drops the detection rate from 95% to 83%.). With selective media, the detection rate with vaginal (not cervical - which would be lower) c/s =x 59%, for rectal c/s= 90%, and both sites = 100%. The Silver & Struminski paper (Prov R.I.) from July '96 AJOG (vol 175:155-7) mentions, in the 'Material & methods', "there is currently only one commercially available prepackaged tube containing Todd- Hewitt broth, and the tube is GLASS, decreasing its value as a transport tube." These investigators used a bit of innovation to prepare their own sterile plastic selective direct inoculation tubes and did a cost-analysis comparison. (Incidentally the Boyer study - NEJM 1986 {324:1665-9} - upon which the AAP based their 28 wk screening recc's, used direct inoculation onto selective growth media technique.)

For clarification purpose (as well as making a new paragraph in case Mats is reading), the policy was not designed to avoid all intrapartum GBS sepsis. The June 1996 ACOG comm opinion (pg 10, bottom left) describes the efficacy of the two strategies, and the associated chemoprophylaxis treatment burden. Late prenatal cultures will treat 27% of pts and prevent 86% early onset GBS. Using risk factor strategy will treat 18% and prevent 68% EARLY ONSET GBS. I'm not sure if it was You, or Joe (the man), or WHO? mentioned it - but someone pointed out a few months back -- these strategies are aimed at intrapartum prophylaxis of EARLY ONSET sepsis, some babies are already quite ill on presentation. The pediatric meningitis lit in the recent past is looking at cytokine-mediated neural damage - in some cases the bacterial burden is so great that the inflammatory response upon initiating antibiotic therapy not only seals the fate, but may hasten it. (Interestingly, they're looking at steroids - but that's another topic.)

It seems the best we can do is remain aware of what we are aiming therapy at with intrapartum prophylaxis. To be aware of the pitfalls in diagnosis and utilize optimal culture practices when this strategy is chosen. And try and find ways to improve things, when we can. For example, the Mclaren study from Illinois (AJOG 6/96, vol 174:1934-37) tried to fine-tune their assignment of risk factors. They analyzed 21 cases of GBS sepsis from a catchment of 9 hospitals over an 18 month period. The denominator was 10,021 for an incidence of 2.1/1000. Dx based on positive cultures in CSF/Urine/Blood accomp by need for fluid or dopamine for maintaining bp. Only 2 of the 21 (10%) met the CDC criteria for risk factor chemoprophylaxis. When they reduced the interval of ROM to greater than 10 hrs (instead 18 hrs), they were able to pick up 13/21 cases. This then compares favorably to the 0.5/1000 incidence of GBS sepsis in the group undergoing antenatal culture and intrapartum abtc protocol.

Of course, flavoring apple Odwalla with ampicillin's no panacea, as it won't be long before bacterial resistance and anaphylaxis begins to show up on our list. But to throw an idea out ("no 'Mr Bill', not the trashbin"...) has anyone considered an algorithm based on population prevalence? For instance, in sites where GBS has replaced the lactobacillus as 'nml flora' would culture strategy be best. While those with rare cases, or in whom less than optimal culture protocols might be subject to litigious scrutiny, perhaps risk factor strategies might prevail?

Whatever the decision, keep in mind these strategies are allowing more than half of at-risk infants the opportunity to enjoy their first wks at home with their parents, rather than in the NICU. Someday we'll better define "at risk", and help even more. Anyone interested in Cerebral Palsy, periventricular leukomalacia, and CNS infection, as related to IL-6, TNF-a, and Il-1b mediated coagulative necrosis in CNS white matter see Yoon AJOG 174:1433. T Jones.

I would like to hear comments from the list re: 2 recent articles. Patel, Leblanc, Morrison et al. South Med J 1994;87:1117 Out of the U. of Mississippi & Siegel and Cushion Obstet Gynecol 1996;87:692 Out of Parkland

These both deal with postnatal penicillin G to the neonate to prophylax against early onset GBBS. In both studies, the single dose to the newborn reduced the incidence of early onset GBBS by 50%. This is similar to the results reported with culturing and then treating colonized mothers during labor. Cost $0.17 per delivery. That is cost not charge. Can anybody out there get a culture for $17.00 ???

I agree with your point about this being a protocol with known and anticipated false negatives and that prevention of many but not all GBS sepsis is to be expected. My point was that these babies did develop early GBS disease despite culture. If they had not been cultured, severe criticisms would have prevailed against the risk factor arm of the protocol and although suits are possible no matter what, I think it would be much more likely had cultures not been done.

If we are to adopt a screening protocol, we should be culturing all patients. At Baylor, all patients undergo vaginal/rectal culture with selective media at 35 - 37 weeks.

I remember when we used to "screen" for gestational diabetes and hepatitis B based on risk factors before we realized the error of our ways and moved to universal "screening".

Selection for antibiotics in labor, theoretically would prevents 86% of cases using routine cultures and 68% of cases using "risk factors". Both percentages were listed in the ACOG guidelines. I think it is only a matter of time until a neonate dies of GBS sepsis and a lawyer elects to query the provider why he/she chose the less effective preventative strategy.

At our 400 delivery/year rural hospital we culture everyone at 35 wks and treat all positives in labor. Women how present with premature labor prior to 35 wks all get cultured on admission and treated with antibiotics empirically.

I don't know which studies ACOG bases their recommendations on but I doubt there are that many, if any, longitudinal investigations comparing outcome with culturing from different locations or with different methods with differing sensitivity. It is possible that clever culturing might raise the rate of positive's considerably, calling for treatment of the greater part of the pregnant population, without improving the overall outcome one bit, since there is very likely a strong relationship between the infective dosage and risk of clinical infection.

Strictly speaking, the benefit of intervention has only been shown for those methods/sites of culturing that were used in the relevant studies.

"criteria for risk factor chemoprophylaxis. When they reduced the interval of ROM to greater than 10 hrs (instead 18 hrs), they were able to pick up 13/21 cases."

If you reduce it to 10 minutes you would pick up close to 21/21 cases. The infective dosage is depending on the ROM interval to some degree, but this kind of statistics doesn't really reveal the point of discrimination based upon cause-effect, but mostly shows that the mean interval of labor after ROM is shorter than 18 hours.

I have never had a baby w/GBS problems. This is not to say that I have never had a mom or a baby positive for GBS, I have.

My protocol is this, I give information on the screening process.

If my client chooses to be screened and is positive, then there are 5 choices.

  1. do nothing
  2. schedule a hospital delivery with the routine IV antibiotics in labor
  3. oral antibiotics 10d to 2 weeks prior to EDC
  4. herbal antibiotic treatment prior to EDC
  5. give baby herbal antibiotics after birth
This information and the choices are given in written form and a signed copy is kept by both the parents and in the chart.

This Web page is referenced from another page containing related information about Group B Strep (GBS) aka Beta Strep


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