[SP1 serum levels in pregnancy with Rh isoimmunization]

The authors examined in 37 pregnant women hospitalized on account of Rh incompatibility during the second and third trimester 71 serum specimens for levels of trophoblast specific beta 1-glycoprotein (SP1), using the method of simple radial immunodiffusion. In the group of 16 women with Rh incompatibility whose pregnancy terminated by delivery of a normal neonate, in 22% the SP1 levels were higher than 1.5 x the median value for the given gestation week (MoM). In 17 pregnancies where the foetus suffered from haemolytic disease the SP1 levels were higher than 1.5 MoM in 45% of the examined foetuses. Markedly elevated SP1 levels of 2.3 and 2.4 MoM were recorded in two pregnancies with hydrops of the foetus.