Research showed that 60% of infants infected with gbs are born to mothers who tested negative in the course of the pregnancy. This may be as a result of how expecting mothers are screened. Ordinarily testing for the existence of the gbs bacteria is performed between the 35th and 37th week of the pregnancy. Based on the report roughly 85 percent of pregnant women are tested.
But the Group B Strep bacteria can colonize after the woman is tested but prior to labor and delivery. In such situations, antibiotics will typically not be given by doctors. This means that the danger that the bacteria will be transmitted from mother to child and that the baby will get the gbs infection is not eliminated.