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GBS Prophylaxis — USMLE Step 2 CK MCQ

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MediumObstetrics & GynecologyGBS ProphylaxisUSMLE Step 2 CK

A 30-year-old with penicillin allergy (hives) needs GBS prophylaxis in labor; prior culture shows GBS susceptible to clindamycin. Best regimen?

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Correct answer: D — Clindamycin IV (if susceptible)

For high-risk penicillin allergy, clindamycin can be used only if the isolate is susceptible. Cefazolin is for low-risk allergy; vancomycin is for resistance or unknown susceptibility; no prophylaxis is unsafe.

Reference: ACOG Committee Opinion (2020): Prevention of Early-Onset GBS Disease in Newborns