Anti-D (Rho) Immunoglobulin

The development of anti-D antibodies generally results from feto-maternal haemorrhages (FMH) occurring in Rhesus D (RhD) negative women who carry a RhD positive fetus. In later pregnancies anti-D antibodies can cross the placenta, causing worsening rhesus haemolytic disease with each successive Rh positive pregnancy.¹

For further information on the aetiology, epidemiology, presentation, investigation and differential diagnosis see our dedicated article on Haemolytic Disease of the Newborn.

Preparations licensed for use in the UK are:

• D-GAM ® (Bio Products Laboratory): available as 250, 500 and 2500 iu vials, for intramuscular use only.²
• Partobulin SDF ® (Baxter Bioscience): available as 1250 iu prefilled syringe, for intramuscular use only.³
• Rhophylac ® (ZLB Behring): available as 1500 iu prefilled syringe, for intramuscular or intravenous use.⁴
• WinRho SDF ® (Cangene Corporation): available as 1500 iu and 5000 iu vials, for intramuscular or intravenous use.⁵

The European Agency for the Evaluation of Medical Products has produced a core anti-D Summary of Product Characteristics (SPC).⁶ Licensed use and dosage regime vary between products so see individual SPCs or the manufacturer's information where available. NICE recommend that the product with the lowest acquisition cost should be used.¹

Routine Antenatal Anti-D Prophylaxis (RAADP)

• All pregnant women who are RhD negative should be offered anti-D providing they are not known to be sensitised to the RhD antigen. Depending on the preparation used this can be given as two doses (one at 28 weeks and one at 34 weeks gestation), or as a single dose between 28 and 30 weeks gestation.
• RAADP should be offered even if it was given prophylactically for a sensitising event earlier in the same pregnancy.
• All RhD negative women who give birth to a Rh positive baby should be offered anti-D 72 hours after delivery.

Administration after a sensitising event^1,6

• Abortion/threatened abortion, ectopic pregnancy or hydatidiform mole
• Transplacental haemorrhage (TPH) resulting from ante-partum haemorrhage (AMH), amniocentesis, chorionic biopsy or obstetric manipulative procedures e.g. external version, or abdominal trauma
• Treatment of Rh(D)-negative persons after incompatible transfusions of Rh(D)-positive blood or other products containing red blood cells

Hypersensitivity to any of the components.

The patient should be observed for twenty minutes after the injection to exclude the development of an anaphylactic reaction. The name and batch number should always be recorded. In the unlikely event of a subsequent identification of an infected batch of this blood product, the patient can be checked.

• Active immunisation with live virus vaccines (e.g. measles, mumps or rubella) should be deferred until 3 months after the last administration of anti-D immunoglobulin, as the efficacy of the live virus may be affected. If anti-D immunoglobulin needs to be administered within 2-4 weeks of a live virus vaccination, then the efficacy of such a vaccination may be impaired.
• After injection of immunoglobulin the transitory rise of the various passively transferred antibodies in the patients blood may result in misleading positive results in serological testing.
• The results of blood typing and antibody testing including the Coombs or antiglobulin test, are significantly affected by the administration of anti-D immunoglobulin.

• Local pain and tenderness can occur. This can be limited by dividing larger doses over several injection sites.
• Fever, malaise, headaches, cutaneous reactions and chills can occur.
• Rarely, nausea, vomiting, hypotension and tachycardia have been reported.
• Allergic or anaphylactic reactions can include dyspnoea and shock. There may be no history of hypersensitivity to a previous injection.