Group B Strep (GBS) is a type of bacteria that causes
problems for pregnant women and their newborns. It
is most often found in the vagina, rectum and is sometimes
detected in the initial urine culture performed at
the first prenatal visit. Usually the test is performed
between weeks 35 and 37. a baby who becomes infected
with Group can become seriously ill; the baby may
end up with blood, lung, brain and spinal cord infections.
The fatality rate is 5%.
What does the test
involve?
A woman is typically tested between weeks 35 &
37; there is some controversy on the timing because
although she may test negative earlier she may in
fact be tested positive at the time of labor. Some
doctors forgo the screening and treat any pregnant
woman with the following risk factors with antibiotics
during labor:
• Preterm labor
• Preterm rupture of membranes
• Prolonged rupture of membranes (membranes
have been ruptured for more than 18 hours before baby
is born)
• Has previously delivered baby with GBS
• Has fever during labor
• Has previously tested positive for GBS in
a prenatal urine culture (Note: a woman tested positive
for Strep B but undergoing C-section need not be on
antibiotics during labor if her delivery occurs before
labor begins or rupture of membranes occurs)
What is the procedure
like?
It involves taking a culture from the vagina, perineum,
and rectum during pregnancy. Results take 2 days.
If your test comes positive (you are carrying the
bacteria) you should take antibiotics during delivery
to minimize the risk of passing the infection on to
your baby.
