Serial aggressive platelet transfusion for fetal alloimmune thrombocytopenia: platelet dynamics and perinatal outcome.

Abstract

Our purpose was to describe the fetal loss rate and platelet dynamics in fetal alloimmune thrombocytopenia managed by serial platelet transfusions. Retrospective analysis over 10 years of consecutive pregnancies affected by fetal alloimmune thrombocytopenia requiring in utero platelet transfusions. There were 2 perinatal losses in 12 pregnancies managed by 84 platelet transfusions. One was obviously procedure related from exsanguination despite platelet transfusion. The attributable procedure related fetal loss rate was 1.2% per procedure but 8.3% per pregnancy. The median rate of fall in fetal platelet count per day after transfusion was lower at the placental cord insertion (n = 54) 40.5 x 10(9)/L (range, 5.4-96.1 x 10(9)/L) compared with that at the intrahepatic vein (n = 30) 50.9 x 10(9)/L,(range, 29.5-91 x 10(9)/L) (P = .0009). Pooling our results with those previously published yields a cumulative risk of serial weekly transfusions of approximately 6% per pregnancy, indicating the need for development of less invasive approaches.