[Granulocyte-specific and HLA antibodies in pregnancy: incidence and clinical value].

Postpartum sera of 1,016 unselected women were examined for granulocyte-specific and HLA antibodies. A total of 11 out of 1,016 sera (1.1%) were only reactive with neutrophils. Cytotoxic HLA antibodies were detected in 24%, noncytotoxic HLA antibodies in 4.8% of the sera. All antibodies belonged to the IgG 1 and IgG 3 subclasses. NA1 and NB1 specificity were each determined in one serum, two sera contained NA2-specific antibodies. After 1 year all antibodies were no more detectable. As none of the newborns from immunized mothers developed neutropenia, the incidence of alloimmune neonatal neutropenia seems to be lower than 0.1%.