Maternal anti-D prophylaxis during pregnancy does not cause neonatal haemolysis

Objective-To evaluate signs of haemolysis in babies of Rh-D negative mother s who underwent prophylaxis with anti-D immunoglobulin during pregnancy. Design-The following were evaluated in all babies of Rh-D negative mothers born within a three month period in our department: haemoglobin level, pack ed cell volume, mean corpuscular volume, reticulocytes, bilirubin level, an d direct Coombs' test (direct anti-globulin test). The babies were divided into two groups according to number of doses of anti-D immunoglobulin recei ved by the mother (one or two), and then further divided by their Rh status (negative or positive). Findings were also compared with a control group o f babies of O-Rh positive mothers. Results-The study group consisted of 101 babies and the control group of 37 babies. No statistically significant differences were found for any of the haematological variables between the babies of mothers who received one or two doses of anti-D immunoglobulin, or between the Rh negative babies (n = 35), and the controls. Although 20% of the Rh positive babies born to moth ers receiving two doses of anti-D immunoglobulin had a positive result in t he direct Coombs' test compared with only 2.4% of the babies of mothers tre ated with only one dose, no signs of haemolysis were documented in the babi es with a positive Coombs test. Conclusion-The prevention of Rh isoimmunisation with anti-D immunoglobulin (one or two doses) during pregnancy does not jeopardise the newborn. Blood group typing and direct Coombs' test should be performed in every newborn o f an Rh negative mother to establish whether there is a necessity to admini ster anti-D. In the presence of a positive direct Coombs' test, the type of antibodies should be identified.