Anti-D Immunoglobulin

• Routine antenatal prophylaxis at 28 weeks
• Sensitising events in pregnancy
• Within 72 h of delivery if neonate RhD+

Passive antibody coats fetal RhD+ red cells in maternal circulation → cleared before they trigger active immune response.

• Always within 72 h of event
• 500 IU IM standard UK antenatal dose
• Kleihauer test if >20 wks to size FMH

Routine antenatal (RAADP)

1500 IU IM at 28 wks OR 500 IU at 28 + 34 wks

Sensitising event ≤20 wks

250 IU IM within 72 h

Sensitising event >20 wks

500 IU IM + Kleihauer for top-up

Post-delivery

500 IU IM if neonate RhD+, within 72 h

• AbsolutePatient already sensitised (anti-D antibodies present)
• CautionSevere thrombocytopenia (IM route)

• Local injection site reaction
• Rarely anaphylaxis
• Mild fever, headache

• • No fetal risk — IgG crosses placenta but at non-clinical dose.
• • Prevents haemolytic disease of fetus & newborn in future pregnancies.

• Live vaccines (MMR, varicella)

  Caution

  Delay 3 months after anti-D

• 💡 Never withhold for cffDNA delays >72 h.
• 💡 Document batch number in maternal notes.