Two ways are used to select female candidates to IAP: the culture-based screening approach and the risk-based approach. The culture-based screening approach identifies candidates using lower vaginal and rectal cultures obtained between 35 and 37 weeks of gestation (or 36-37), and IAP is administered to all GBS colonized women. The risk-based strategy identifies candidates to receive IAP by the aforementioned risk factors known to increase the probability of GBS-EOD without considering if the mother is or is not a GBS carrier.