Maternal anti-HLA class I antibodies are associated with reduced birth weight in XXXX neonates.

@entity1 @entity16978 @entity882
UNASSIGNED: In this comparative cross-sectional study, possible associations between maternal anti-HLA class I antibodies and birth weight in @entity882 are explored. Although commonly detected in pregnancies and generally regarded as harmless, it has been suggested that such antibodies might be associated with @entity16978 ( @entity16978 ). As a link between @entity16978 due to human platelet antigen 1a-specific antibodies and reduced birth weight in @entity1 has previously been demonstrated, we wanted to explore whether maternal anti-HLA class I antibodies might also affect birth weight. To examine this, suspected cases of @entity16978 referred to the Norwegian National Unit for Platelet Immunology during the period 1998-2009 were identified. Pregnancies where the only finding was maternal anti-HLA class I antibodies were included. An unselected group of pregnant @entity1 participating in a prospective study investigating maternal-fetal hemodynamics at the University Hospital North Norway during the years 2006-2010 served as controls. Twenty-nine percent of controls had anti-HLA class I antibodies. The @entity882 neonates had a significantly lower adjusted birth weight (linear regression, P=0.036) and significantly higher odds of being small for gestational age (OR=6.72, P<0.001) compared with controls. Increasing anti-HLA class I antibody levels in the mother were significantly associated with lower birth weight and placental weight among @entity882 neonates, but not among controls. These results indicate that maternal anti-HLA class I antibodies in @entity882 neonates are associated with reduced fetal growth. Further studies are needed to test if placental function is affected.
