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Obstetrical#antepartum#labor#triage#medications#pretermPGY 1/2/3/4

Preterm Labor: Steroids, GBS, Mag Neuroprotection, Tocolysis

Steroid windows (22w5–34w + ALPS 34–36w6), GBS prophylaxis, mag neuroprotection by GA, tocolysis (indomethacin vs nifedipine).

Source: PGY-1 Resident Handbook 2026-2027

Steroid courses:

  • 22w5d–23w5d — situational, depends on patient/provider preference (wait for joint NICU/MFM counseling).
  • 24–34 wks — everyone gets BMZ 12 mg IM q24h × 2 doses.
  • 34w0d–36w6d — ALPS counseling. DO NOT tocolyze for steroids, but in stable PPROM, can delay augmentation × 12h.

GBS prophylaxis (if positive or unknown):

  • Ampicillin 2 g IV initial dose, then 1 g IV q4h until delivery.

Mag neuroprotection (viability up to 31w6d, for 12 hours, if delivery imminent):

  • ≥ 26 weeks: load 6 g, then 2 g/hr
  • < 26 weeks: load 4 g, then 2 g/hr

Tocolysis:

  • IV fluid bolus 1–2 L over 1–4 hours.
  • 23w0d–31w6d: Indomethacin — 50 mg loading dose, then 25 mg PO q6h for total of 48 hours.
  • 32w0d–33w6d: Consider nifedipine — 20 mg IR PO loading dose, then 10 mg IR PO q6h × 48 hours.

Referenced by handoffs