It takes about 24 hours to do a bacterial culture for a group B streptococcus infection. When a patient is infected with group B streptococcus, it may cause endocarditis, neonatal sepsis, pneumonia, meningitis, hydrocephalus, mental retardation, etc. Meanwhile, group b streptococcus can also cause pregnant women to experience preterm labor, late miscarriage, and premature rupture of membranes. To determine whether a patient is infected with group B streptococcus, a bacterial culture of the secretion is needed; normally it takes about 24 hours to do a bacterial culture of the secretion. After 24 hours of culture, if group B streptococcus is cultured, then it means that the patient is infected with group B streptococcus; so that the doctor can advise the patient to use the appropriate antibiotics for treatment according to the results of the bacterial culture. The patient should try his best to cooperate with the doctor’s treatment, and if at any time there is any special discomfort to seek medical attention as soon as possible.