Infections in pregnancy: group B streptococcus: practice question

A OBG question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

OBG · Infections in pregnancy: group B streptococcus

Sample item

A woman in spontaneous labour at 38 weeks has a positive rectovaginal swab for group B streptococcus at 36 weeks and no penicillin allergy. What is the appropriate intrapartum prophylaxis?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

C. Intravenous benzylpenicillin (penicillin G) started at the onset of labour and repeated every 4 hours until delivery

Intrapartum intravenous penicillin G, given at least 4 hours before delivery, reduces early-onset neonatal GBS sepsis. Oral antibiotics antenatally do not eradicate colonisation, and prophylaxis is indicated in all colonised women in labour, regardless of gestation. Cefazolin is used in low-risk penicillin allergy.

Option by option

  • A. No prophylaxis because she is at term

    Term gestation does not remove the need for prophylaxis in a carrier.

  • B. Oral amoxicillin 500 mg thrice a day for 5 days

    Antenatal oral antibiotics do not eliminate carriage and are not recommended.

  • C. Intravenous benzylpenicillin (penicillin G) started at the onset of labour and repeated every 4 hours until delivery (correct)

    Correct. IV penicillin G in labour is the standard prophylaxis.

  • D. Single-dose intramuscular gentamicin

    Aminoglycoside alone is inadequate and not recommended.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More OBG questions

Questions about this OBG question

What is the answer to this OBG question?

The best answer is C, Intravenous benzylpenicillin (penicillin G) started at the onset of labour and repeated every 4 hours until delivery. Intrapartum intravenous penicillin G, given at least 4 hours before delivery, reduces early-onset neonatal GBS sepsis.

Why is "No prophylaxis because she is at term" not the answer?

Term gestation does not remove the need for prophylaxis in a carrier.

Why is "Oral amoxicillin 500 mg thrice a day for 5 days" not the answer?

Antenatal oral antibiotics do not eliminate carriage and are not recommended.

Why is "Single-dose intramuscular gentamicin" not the answer?

Aminoglycoside alone is inadequate and not recommended.

What concept does this question test?

It tests Infections in pregnancy: group B streptococcus in OBG. Oral antibiotics antenatally do not eradicate colonisation, and prophylaxis is indicated in all colonised women in labour, regardless of gestation. Cefazolin is used in low-risk penicillin allergy.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Infections in pregnancy: group B streptococcus?

Learn management algorithms as steps: PPH, eclampsia, ectopic pregnancy. Then use the flashcards and the other OBG questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.