FETAL PLASMA ERYTHROPOIETIN CONCENTRATIONS IN INTRAUTERINE TRANSFUSION THERAPY OF ISOIMMUNOHAEMOLYTIC ANEMIA DUE TO RH DISEASE

Purpose: Prenatal plasma concentrations of erythropoietin in fetuses w ith Rh disease should contribute information to the clinical course an d therapeutic control of this disease. Method: Fetal plasma erythropoi etin (Epo) and haemoglobin (Hb) concentrations were measured in 145 um bilical venous blood samples of 30 fetuses with Ph disease at 20 to 38 weeks' gestation. Results: Both Epo and Hb concentrations were indepe ndent of the gestational age in red blood cell-isoimmunised pregnancie s. The Hb concentration correlated significantly with Epo concentratio n without intrauterine transfusion (IUT) (r = -0.519, p = 0.005) and a fter IUT (r = -0.212, p = 0.01). A haemoglobin deficit of 3 g/dl at 20 weeks' gestation increased to 6 g/dl at 38 weeks' gestation in spite of IUT (p = -0.354, p<0.001). Conclusion: Even with IUT, Epo concentra tions increase with gestational age during these pregnancies. This is due to increasing Hb deficits indicating fetal hypoxia which might be prevented by increasing volumes of transfusion.