Anti-D immunisation with permanent biological damage following inadequate post-amniocentesis prophylaxis.

The most severe form of haemolytic disease of the newborn (HDN) is that caused by anti-D antibodies which form when a Rh D-negative woman gives birth to a D-positive child1. In western countries the incidence of foetal-maternal anti-D immunisation has decreased drastically from the 1960s to the present, in part due to the decrease in birth rate, and is currently the cause of only 4–5 deaths every 100,000 deliveries2. The introduction of anti-D immunoprophylaxis in pregnant Rh D-negative women and the application of recommendations have notably reduced the risks related to maternal alloimmunisation3. The main causes of failed immunoprophylaxis are substantial foetal-maternal haemorrhage (FMH) in the last period of the pregnancy or during delivery, with the administration of insufficient immunoprophylaxis to cover the amount of haemorrhage4. Although quantification of the amount of foetal blood that enters the maternal circulation and adjustment of the doses of anti-D IgG are recommended, these procedures are not always carried out even though guidelines on the prevention, diagnosis, monitoring and treatment of HDN are ever more numerous and well defined5.