FETOMATERNAL HEMORRHAGE FOLLOWING FUNIPUNCTURE - INCREASE IN SEVERITYOF MATERNAL RED-CELL ALLOIMMUNIZATION

Objective: To determine the prevalence of fetomaternal transplacental hemorrhage after funipuncture and its effect on maternal red-cell allo antibody levels.Methods: The prevalence and size of transplacental hem orrhages at the Health Sciences Centre were studied in two groups of p atients: 174 women who were not alloimmunized or were carrying fetuses whose red cells were negative for the antigen to which they were immu nized, and 122 women who were alloimmunized and carrying fetuses whose red cells were positive for the antigen to which they were immunized. In the alloimmunized group with affected fetuses, we surveyed the inc idence of maternal antibody increase in titer by two or more doubling dilutions and the Rh(D) antibody increase (in mu g/mL of serum) of mor e than 50% after funipuncture. Results: One hundred of the 174 women ( 57.5%) in the nonimmunized group and 69 of the 122 women (56.6%) in th e immunized group had evidence of transplacental hemorrhages ranging i n volume from 0.03 mL to greater than 5 mL of fetal red blood cells. I n the latter group, antibody titer increases of 2 to 9 and doubling di lutions occurred in 37 of 74 women (50%) in whom such measurements wer e carried out. Increases of anti-D exceeding 50% occurred in 44 of 53 women (83%) in whom quantitative measurements were assayed. Conclusion : Funipuncture carries a high risk of fetal transplacental hemorrhage. In the immunized woman carrying an antigen-positive fetus, this will increase the level of her antibody and probably increase the severity of hemolytic disease in her fetus. In alloimmunized women, funipunctur e should rarely be carried out to determine the fetal antigen status. Serial amniocenteses combined with careful serial ultrasound observati on of the fetus are safer. Funipuncture should not be done in alloimmu nized women before the cord vessels are of adequate size to allow imme diate intravascular fetal transfusion, if required.