HL‐A Antibodies: Influence on the Human Foetus

Sera from 1,726 pregnant women were investigated for the presence of lymphocytotoxic antibodies. The incidence of antibodies was found to increase significantly with parity. No deleterious effect of maternal HL—A antibodies upon the foetus were found. A total of 113 Rh‐immunized women delivering Rh‐positive children were investigated for the presence of HL‐A antibodies. The incidence of lymphocytotoxic antibodies was significantly higher than among non‐Rh‐immunized women. No correlation were found between demonstrable maternal HL—A immunization and the degree of the haemolytic disease of the newborn due to Rh antibodies.