GBS explained for a friend.
Dec. 1st, 2020 08:59 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
whitewriterWhat is it: Group B streptococcus is a bacteria that lives commonly in the vagina and gastrointestinal tract. It comes and goes, therefore isn't always present - you may test negative one month , and a few months later test positive.
Why is it significant in obstetrics:
A woman has a choice regarding if they want to be tested for GBS or not. If you are not tested for GBS, you will be classed as GBS unknown. If you have no risk factors for GBS (aka. you go into labour, your waters break whilst your in labour, and you have a normal vaginal birth) you won't be given any special treatment for GBS (Regardless of your status).
If you choose to be tested at 36 weeks for GBS and test positive, then you will be given an IV cannula as soon as you start labour, and you will be given antibiotics every 6 hours until you deliver. this could mean 1 dose of 3g benzylpenicillin, followed by 1.8 grams 6 hourly. So for example if you birthed in 3 hours you would only get 1 dose (the loading dose), but if you birthed in say 12 hours you would get about 3 doses (1 at the beginning, then at 6 hours and then at 12 hours). The more doses you get the more prevention occurs - compared to if you only get 1 dose.
The plastic canula in your hand is annoying and can distract you when your likely to want to be focusing on other things.
If your GBS positive and come into the hospital and birth before we can put the canula in (lets say, within 30 mins) then your baby would get extra observations by the midwives on maternity ward to ensure everything was okay.
Each district and hospital has a different policy regarding testing women for GBS in the vagina via a swab at approx 35-37 weeks gestation.
For example, SSH tests everyone at 36 weeks.
Meanwhile just 4 km down the road (within the same district) MSH tests only those with risk factors for contracting GBS (for example, waters breaking early before labour commences-- or previous neonatal sepsis from GBS -- in which case they may not even bother testing for it, and just prescribe the antibiotics anyways and recommend the woman have them).
This means that women at SSH are more likely to get antibiotics in labour, than those at MSH.
Other important facts:
Incidence overall is 0.5/1000 births
Of these 1 in 2000 babies that are infected, 4-6% die.
In 80% of these cases, the symptoms of early onset GBS (EOGBS) are seen in the first 6 hours of life.
In 90-97% of cases, symptoms are evident in the next 24 hours of age.
The evidence suggests that more than 60% of confirmed cases of neonatal EOGBS sepsis are born to women who had a negative GBS culture at 35-37 weeks gestation.
Also worth noting late-onset GBS can occur from 7 days of age to 3 months of age. (When your caring for your baby at home).
Whilst intravenous antibiotics is the most reliable method of reducing incidence of neonatal EOGBS, its use has not been shown to significantly reduce the incidence of late onset GBS, neonatal mortality from GBS sepsis or neonatal mortality from sepsis caused by bacteria other than GBS.
Why is it controversial?
>international consensus has not been reached regarding the best way to prevent neonatal GBS.
>There is limited high quality evidence for either approach (routine swab versus a risk factor based approach).
Main source of information:
https://www1.health.nsw.gov.au/pds/ActivePDSDocuments/GL2017_002.pdf
https://www.cdc.gov/groupbstrep/about/fast-facts.html
Singh, T., Barmes, E.H., Isaacs, D. (20019) Early-onset neonatal infections in Australia and New Zealand, 2002-2012. Archives of Disease in Childhood. 104(3) F248-F252.
( https://pubmed.ncbi.nlm.nih.gov/29588295/#:~:text=Group%20B%20streptococcus%20(GBS)%20(,%25%20with%20early%2Donset%20E.)
Whist I am not against antibiotics by any means, I am fully against the misuse of antibiotics, which can cause:
>diarrhea and gastrointestinal problems in yourself and your baby in later life.
>increased possibility of promoting resistant strains of bacteria in your own body, limiting their effectiveness in the future.
Just because you have GBS in one pregnancy does not mean that you will have it in the next. However if you've had one baby infected with GBS, you will certainly be advised to have IVABs for any future children (and I would agree that's sensible).
If a risk factor was present (early broken waters for example). I'd advocate here for the use of IVABs.
However if that's not the case, if your completely low risk: considering that just down the road in the same district, another hospital is not routinely doing swabs, I would strongly question the need to accept a swab just because I was offered it.
Why is it significant in obstetrics:
A woman has a choice regarding if they want to be tested for GBS or not. If you are not tested for GBS, you will be classed as GBS unknown. If you have no risk factors for GBS (aka. you go into labour, your waters break whilst your in labour, and you have a normal vaginal birth) you won't be given any special treatment for GBS (Regardless of your status).
If you choose to be tested at 36 weeks for GBS and test positive, then you will be given an IV cannula as soon as you start labour, and you will be given antibiotics every 6 hours until you deliver. this could mean 1 dose of 3g benzylpenicillin, followed by 1.8 grams 6 hourly. So for example if you birthed in 3 hours you would only get 1 dose (the loading dose), but if you birthed in say 12 hours you would get about 3 doses (1 at the beginning, then at 6 hours and then at 12 hours). The more doses you get the more prevention occurs - compared to if you only get 1 dose.
The plastic canula in your hand is annoying and can distract you when your likely to want to be focusing on other things.
If your GBS positive and come into the hospital and birth before we can put the canula in (lets say, within 30 mins) then your baby would get extra observations by the midwives on maternity ward to ensure everything was okay.
Each district and hospital has a different policy regarding testing women for GBS in the vagina via a swab at approx 35-37 weeks gestation.
For example, SSH tests everyone at 36 weeks.
Meanwhile just 4 km down the road (within the same district) MSH tests only those with risk factors for contracting GBS (for example, waters breaking early before labour commences-- or previous neonatal sepsis from GBS -- in which case they may not even bother testing for it, and just prescribe the antibiotics anyways and recommend the woman have them).
This means that women at SSH are more likely to get antibiotics in labour, than those at MSH.
Other important facts:
Incidence overall is 0.5/1000 births
Of these 1 in 2000 babies that are infected, 4-6% die.
In 80% of these cases, the symptoms of early onset GBS (EOGBS) are seen in the first 6 hours of life.
In 90-97% of cases, symptoms are evident in the next 24 hours of age.
The evidence suggests that more than 60% of confirmed cases of neonatal EOGBS sepsis are born to women who had a negative GBS culture at 35-37 weeks gestation.
Also worth noting late-onset GBS can occur from 7 days of age to 3 months of age. (When your caring for your baby at home).
Whilst intravenous antibiotics is the most reliable method of reducing incidence of neonatal EOGBS, its use has not been shown to significantly reduce the incidence of late onset GBS, neonatal mortality from GBS sepsis or neonatal mortality from sepsis caused by bacteria other than GBS.
Why is it controversial?
>international consensus has not been reached regarding the best way to prevent neonatal GBS.
>There is limited high quality evidence for either approach (routine swab versus a risk factor based approach).
Main source of information:
https://www1.health.nsw.gov.au/pds/ActivePDSDocuments/GL2017_002.pdf
https://www.cdc.gov/groupbstrep/about/fast-facts.html
Singh, T., Barmes, E.H., Isaacs, D. (20019) Early-onset neonatal infections in Australia and New Zealand, 2002-2012. Archives of Disease in Childhood. 104(3) F248-F252.
( https://pubmed.ncbi.nlm.nih.gov/29588295/#:~:text=Group%20B%20streptococcus%20(GBS)%20(,%25%20with%20early%2Donset%20E.)
Whist I am not against antibiotics by any means, I am fully against the misuse of antibiotics, which can cause:
>diarrhea and gastrointestinal problems in yourself and your baby in later life.
>increased possibility of promoting resistant strains of bacteria in your own body, limiting their effectiveness in the future.
Just because you have GBS in one pregnancy does not mean that you will have it in the next. However if you've had one baby infected with GBS, you will certainly be advised to have IVABs for any future children (and I would agree that's sensible).
If a risk factor was present (early broken waters for example). I'd advocate here for the use of IVABs.
However if that's not the case, if your completely low risk: considering that just down the road in the same district, another hospital is not routinely doing swabs, I would strongly question the need to accept a swab just because I was offered it.
