In the final stretch of pregnancy, between weeks 35 and 37, the gynecologist sends a routine test to the pregnant woman to find out if she has group B streptococcal infection , which is known as a “streptococcal test.”
Group B streptococci are bacteria that can be in the vagina of healthy women, to whom it does not cause any harm. But the baby passing through the birth canal could become infected and the infection in the newborn can be complicated. Between 10% and 30% of pregnant women carry the bacteria group B streptococcus (GBS).
Who is affected by strep?
GBS is one of many bacteria that live in the body and do not usually cause serious illness. It is found in the digestive, urinary and reproductive systems of men and women and in women it can be lodged in the vagina and rectum.
Most pregnant women who are colonized with GBS do not have symptoms or their health is affected, but some may develop a urinary tract infection or infection of the uterus caused by the bacteria.
Then the most serious health effect can occur: the infection is transmitted to the baby in the final stage of pregnancy. For this reason, medical organisms have agreed on these recommendations on streptococcal infection that prevent infection of the newborn:
- Perform a vaginal and anal culture to all pregnant women between weeks 35 and 37 of gestation. Cultures older than five weeks may not be valid, so if delivery is delayed they will have to be repeated.
- If the pregnant woman has been infected with group B streptococci or a previous child was infected, prophylactic measures will be carried out directly.
- In cases in which the culture or urine analysis during pregnancy gave positive results and in mothers with previously infected children, intrapartum antibiotic prophylaxis is indicated for the prevention of neonatal infection.
How is the strep test performed?
The streptococcal pregnancy test is performed similarly to a Pap smear, examining samples from the vagina and rectum using a smear . It is a painless procedure. This procedure will take samples of cells from the lower part of the vagina and rectum and send them to a laboratory to grow in a culture that will identify if strep bacteria are present.
Results are available in two to three days, and women who test positive are given intravenous antibiotics during labor to prevent infection of the newborn. Antibiotics help kill these bacteria that can be harmful during labor. If given before delivery, they are likely to reproduce.
On the other hand, if germs are detected in the urine in any of the tests during pregnancy, oral antibiotics are prescribed and a test is carried out at the end of the treatment to see if the GBS has disappeared. But it is likely that residues of the bacteria remain in the genital area, or that the bacteria invade the genital area later.
If the urine contains group B streptococcus, it is a sign that there is a significant amount of that bacteria in the genital area, so antibiotics are usually given intravenously automatically during labor.
The tests prior to week 35 cannot predict whether the woman will be a carrier of the bacteria at the time of delivery, so it is done in that final stage. If delivery is delayed beyond 40 weeks, your doctor may send another test to make sure strep is still free, as discussed above.
If the woman already had a previous pregnancy and was treated for streptococcus, it is likely that they will not retest with subsequent children and the gynecologists will directly recommend the treatment.
If symptoms of streptococcal infection are observed in babies once they are born (not all babies exposed to GBS become infected) and an infection is suspected, treatment with antibiotics active against streptococcus is started. Subsequent treatment will depend on the clinical course and the diagnostic evaluation.
Most babies recover completely, although in some they can present complications, even in the most serious cases to death.
Ultimately, in order to avoid these risks, group B streptococcus bacteria are tested in the final stages of a woman’s pregnancy .
In Babies and more | Fetal monitoring before delivery, what is it for?
