Inpatient Obstetric Nurse (NCC) Practice Exam

Administering the vaginal-rectal swab for Group B Streptococcus (GBS) is typically performed at 35-37 weeks of gestation. This timing is crucial because screening at this stage is optimal to identify carriers of GBS who may potentially transmit the bacteria to their newborn during delivery. The specific window of 35-37 weeks allows healthcare providers to provide appropriate intrapartum antibiotic prophylaxis for women who test positive, significantly reducing the risk of GBS-related infections in neonates.

Earlier screening dates, such as at the first prenatal visit or at 20 weeks of gestation, do not accurately capture the status of maternal colonization, which can change as pregnancy progresses. Similarly, testing during labor is not recommended as it does not allow for timely intervention to protect the infant. The established timeframe of 35-37 weeks strikes a balance between ensuring accurate results and allowing for adequate preparation to address any positive findings.