RCOG GTG 74

Antenatal Steroids & Tocolysis

Preterm labour management

Steroids

  • Betamethasone 12 mg IM, 2 doses 24 h apart (or dexamethasone 6 mg IM × 4 doses q12h).
  • Offer 24⁺⁰–33⁺⁶ / 34⁺⁰–35⁺⁶ if imminent birth.
  • Rescue dose if >7 days since first course and imminent birth <34/40.

Tocolysis

  • Nifedipine 20 mg PO stat → 10–20 mg TDS-QDS (first line, max 48 h).
  • Atosiban if nifedipine contraindicated.
  • Purpose: gain 48 h for steroids + in-utero transfer — not to prolong pregnancy.

Magnesium for neuroprotection

  • MgSO₄ 4 g IV over 20 min → 1 g/h if delivery expected <30/40 within 24 h.

Common mistakes

  • Giving tocolysis to buy time when maternal/fetal indications for delivery exist.
  • Forgetting MgSO₄ neuroprotection <30/40.
  • Betamethasone in uncontrolled infection or diabetes without insulin adjustment.

For educational use only

Not medical advice. Verify dosing against the BNF and your local trust guidelines before prescribing.