THE FORMATION OF HL‐A ANTIBODIES IN PREGNANCY. THE ANTIGENICITY OF ABORTED AND TERM FETUSES

Abstract

Summary A total of 1201 maternal sera obtained before 20 weeks gestation were screened for lymphocytotoxic antibodies directed against HL‐A antigens. Their incidence was 10 per cent in primigravidae, 17 per cent in the second and 22 per cent in third or subsequent pregnancies. Among secundigravidae, strong antibodies were found more often in women having had one live birth (14 per cent), than in those having had only a single abortion (5.6 per cent). It was concluded that the antigenic stimulus from a pregnancy ending in abortion is very weak compared with that of one which goes to term. The relationships between antibody formation and habitual abortion and grande multiparity were explored inconclusively.