Perinatal outcome following intravascular transfusion in severely isoimmunized fetuses

Twenty-six severely isoimmunized pregnancies managed exclusively with ultrasonographically guided intravascular fetal transfusions are reported. The mean gestational age plus and minus one standard deviation (+/- SD) was 26.3 +/- 3.6 weeks and the mean hematocrit (+/- SD) prior to initial transfusion was 20.6 +/- 6.7%. Four of seven hydropic fetuses and 9 of 19 without hydrops were less than or equal to 26 weeks gestation at the first transfusion. Overall survival was 85% (22/26). Survival was similar whether or not fetal hydrops was present (6/7 vs. 16/19) and whether or not the first transfusion was administered at less than or equal to 26 weeks gestation (10/13 vs. 12/13).