RESUMO
INTRODUCTION: Anti-D alloimmunisation may occur from the blood transfusion or fetomaternal haemorrhage which can lead to haemolytic disease of fetal and newborn (HDFN). The morbidity and mortality of HDFN related to anti-D is significantly reduced after introduction of anti-D prophylaxis and furthermore, anti-D HDFN in RhD negative primigravida is uncommonly seen. CASE REPORT: A case of unusual severe HDFN due to anti-D alloimmunisation in undiagnosed RhD negative primigravida Malay woman is reported here. This case illustrates the possibility of an anamnestic response from previous unknown sensitisation event or the development of anti-D in mid trimester. The newborn expired due to hydrops fetalis and severe anaemia. Antenatally, the mother was identified as RhD positive and thus there was no antenatal antibody screening, antepartum anti-D prophylaxis or close fetal monitoring for HDFN. DISCUSSION: The thorough antenatal ABO and RhD blood grouping with antibody screening is mandatory as part of prevention and early detection of HDFN especially due to anti-D alloimmunisation. Improper management of RhD negative women might lead to severe HDFN including in primigravida.