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Question 47
Feto-maternal medicine → Maturity
Classification
Question
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A woman at 29 weeks’ gestation is admitted with a high likelihood of preterm birth and antenatal corticosteroid treatment with dexamethasone phosphate is planned.
Which regimen is an appropriate antenatal corticosteroid course?
Which regimen is an appropriate antenatal corticosteroid course?
Question Stem
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Options
A
Dexamethasone 24 mg as a single intravenous dose
B
Dexamethasone 2 mg orally every 6 hours for four doses
C
Dexamethasone 6 mg intramuscularly every 12 hours for four doses
D
Dexamethasone 6 mg intramuscularly once only
E
Dexamethasone 12 mg orally every 24 hours for two doses
Explanation
Dexamethasone phosphate is an appropriate antenatal corticosteroid for women at risk of preterm birth. A commonly studied regimen is dexamethasone 6 mg given intramuscularly every 12 hours for four doses, producing a total course dose of 24 mg. Dexamethasone is a soluble preparation that is widely used and is included on the World Health Organization Essential Medicines List. Antenatal corticosteroid treatment is given intramuscularly rather than by oral administration, and the total recommended course should not be compressed into an untested single intravenous dose. A single 6 mg dose does not constitute a complete planned course, although treatment may still provide benefit if birth occurs before the full regimen can be completed. When sufficient time is available, the prescribed course should therefore follow an evidence-based intramuscular schedule. Of the regimens presented, four doses of dexamethasone 6 mg at 12-hour intervals is the appropriate regimen and gives the required total dose of 24 mg.
Option Validity
B) Oral dexamethasone is not the recommended route for an antenatal corticosteroid course.
A) A single 24 mg intravenous dose is not the recommended antenatal dexamethasone regimen.
D) A single 6 mg dose does not constitute the standard planned 24 mg course.
E) The recommended antenatal regimen is intramuscular rather than oral dexamethasone.
Further Reading
Stock SJ, Thomson AJ, Papworth S, on behalf of the Royal College of Obstetricians and Gynaecologists. Antenatal corticosteroids to reduce neonatal morbidity and mortality. BJOG. 2022;129:e35–e60. RCOG Green-top Guideline No. 74. doi:10.1111/1471-0528.17027.