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obstetrics-gynaecology

Rh(D) Immune Globulin Dosage for Maternal-Fetal Haemorrhage

Calculates appropriate dose of Rh(D) immune globulin (anti-D) after maternal-fetal haemorrhage in Rh(D)-negative women. Based on Kleihauer-Betke test result. Prevents Rh sensitisation.

Score interpretation

Small FMH (<3 mL) 0–0.0999

Fetal-maternal haemorrhage <3 mL estimated fetal red blood cells

→ Standard prophylactic anti-D: 300 mcg IM (or 1,500 IU); administer within 72 hours of sensitising event; repeat Kleihauer in 48h to confirm adequate coverage; document in maternity notes

Larger FMH — Calculate Dose 0.1–99

Significant fetal-maternal haemorrhage — calculate dose based on KB result

→ Calculate volume = (% fetal cells × maternal blood volume) ÷ 100; administer 300 mcg anti-D per 15 mL fetal whole blood (some guidelines per 30 mL); give IM in divided doses (max 1,500 mcg per site); repeat KB at 48–72h to confirm clearance; haematology involvement for large FMH

Interpretation bands for the Anti-D Dosage. Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.