Selkirk Medical Group
Information for Parents -to-be
What is Group B Streptococcus (GBS)?
GBS is a type of bacteria that is found in the digestive systems of healthy people.
Approximately 10-35% of pregnant women will have GBS in their vaginas at the time
of birth. GBS in the vagina is normal, no symptoms generally appear, and does not
usually cause any health risks to the pregnant woman. Occasionally GBS can cause
a urinary tract infection which needs to be treated.
What is the chance of a baby becoming infected with GBS?
In the general population, GBS disease occurs in 0.5 to 2 per 1000 live births.
How does GBS affect the newborn?
GBS is a significant cause of neonatal morbidity (poor health outcome) and mortality.
In newborns, GBS is a common cause of sepsis (infection in the blood), newborn
pneumonia (infection of the lung) and meningitis (infection of the fluid around the
brain), with the possibility of permanent neurological damage. The mortality rate of
early onset GBS infection (within the first 7 days of life) ranges between 5 to 20%.
What are the risk factors for developing Newborn GBS Disease?
Preterm labour (less than 37 weeks)
Rupture of membranes for greater than 18 hours
Maternal fever in labour
GBS bacteria found in the urine at anytime this pregnancy
History of a previous baby that developed GBS disease
How can GBS disease in the newborn be prevented?
The current recommendation is to screen all
pregnant women for GBS colonization of the
vagina between 35-37 weeks. The screening is
unobtrusive and includes a vaginal-rectal swab
done by the doctor or the women herself. Since
GBS colonization can come and go, testing within
five weeks of the due date is shown to be predictive
of GBS status at time of birth. There is anecdotal
but not scientific evidence that taking good quality
probiotics starting 3 weeks before swabbing for
GBS may result in a lower chance of colonization in
the vaginal area.
If the screening test is positive, IV antibiotics are recommended in active labour or
when your water breaks. Penicillin is the antibiotic of choice, unless known penicillin
allergies exist. If your water breaks before you are in labour, IV antibiotics along with
induction of labour is the current standard. If the screening test is negative, you do
not carry GBS and IV antibiotics will not be necessary.