GBS Risk Assessment for Laboring Female with Unknown GBS Status

Risk Assessment Algorithm

The Centers for Disease Control and Prevention recommends intrapartum antibiotic prophylaxis (IAP) for laboring females with unknown GBS status if any of the following risk factors are present: delivery at <37 weeks' gestation, amniotic membrane rupture ≥18 hours, or intrapartum temperature ≥100.4°F (≥38.0°C) 1, 2, 3
Previous infant with invasive GBS disease is an indication for IAP 1
GBS bacteriuria during any trimester of the current pregnancy is an indication for IAP 1
Unknown GBS status with delivery at <37 weeks' gestation is an indication for IAP 1, 3
Unknown GBS status with amniotic membrane rupture ≥18 hours is an indication for IAP 1, 3
Unknown GBS status with intrapartum temperature ≥100.4°F (≥38.0°C) is an indication for IAP 1, 3
Positive intrapartum NAAT (nucleic acid amplification test) for GBS is an indication for IAP 1

The American College of Obstetricians and Gynecologists recommends that cesarean delivery before labor onset with intact membranes does not require GBS prophylaxis, regardless of GBS status or gestational age 1, 6
Women with suspected amnionitis should receive broad-spectrum antibiotic therapy that includes coverage for GBS rather than GBS prophylaxis alone 1, 3

The Centers for Disease Control and Prevention recommends against administering antibiotics before the intrapartum period to eradicate GBS colonization, as this is ineffective and may cause adverse consequences 1, 3
Do not rely on GBS screening results from previous pregnancies for management decisions in the current pregnancy 1, 3