Diagnosis and treatment of fetal anemia due to isoimmunization.

45 pregnant women affected by rhesus incompatibility were treated at the Department of Prenatal Diagnosis and Therapy, Vienna, between January 1992 and March 1993. 32 patients had a cordocentesis and on 21 fetuses, anemia requiring treatment was diagnosed. A total of 71 intravascular transfusions via the umbilical vein was given. The mean number of transfusions per fetus was 3.4 (range 1-11). Of the 7 fetuses who had already developed hydrops when therapy was started (hematocrit < 13%), 5 (71%) survived. The survival rate of non-hydropic anemic fetuses was 93% (13/14). By using intravascular transfusion for treatment of severe fetal anemia, a success rate of 86% (18/21) was achieved.