THE EFFECT OF THE SOURCE OF TRANSFUSED BLOOD ON THE RATE OF CONSUMPTION OF TRANSFUSED RED-BLOOD-CELLS IN PREGNANCIES AFFECTED BY RED-BLOOD-CELL ALLOIMMUNIZATION

OBJECTIVE: Our purpose was to compare the rate of consumption of mater nally donated red blood cells with the rate of red blood cells from vo lunteers in fetuses affected by red blood cell alloimmunization. STUDY DESIGN: The rate of hemoglobin decline was calculated in 293 fetal tr ansfusions in 52 pregnancies, in 43 patients affected by red blood cel l alloimmunization from 1987 to 1996. Fifty-eight transfusions were ex cluded from analysis. Hemoglobin decline was stratified by gestational age. The rates of consumption were compared with use of unpaired t te sts. RESULTS: The rates of hemoglobin decline (in grams per deciliter per day) were 18 to 24 weeks, 0.47 volunteer and 0.38 maternal lo = 0. 174); 25 to 28 weeks 0.41 volunteer, 0.34 maternal lo = 0.46); 29 to 3 2 weeks, 0.35 volunteer, 0.33 maternal; greater than or equal to 33 we eks, 0.37 volunteer, 0.25 maternal, p = 0.048). Hemoglobin decline was less for the maternal donation group than for the volunteer donation group throughout gestation, becoming significant only in fetuses at gr eater than or equal to 33 weeks. CONCLUSION: In the red blood cell-all oimmunized fetus, there is less consumption of maternal than of volunt eer red blood cells. This difference reaches a statistical significanc e only in late gestation.