Objective: To assess the value of ultrasonography and Doppler to predict the severity of fetal haemolytic anaemia.
Design: Ultrasonographic measurements of the fetal liver, spleen, umbilical vein and placenta, and Doppler measurements of umbilical venous and fetal aorta flow velocities were performed before the first intrauterine blood transfusion. Multivariate regression models for the prediction of the fetal haemoglobin level were derived from the measurements.
Setting: National referral centre for management of alloimmunised pregnancies.
Subjects: Forty fetuses in 39 severe red cell alloimmunised pregnancies.
Results: A logistic regression model, incorporating the two Doppler parameters only, predicted the presence or absence of severe anaemia in nonhydropic fetuses with an accuracy of 90%. Positive predictive value was 89% and negative predictive value was 100%.
Conclusion: In severe red cell alloimmunised pregnancies, Doppler blood flow velocity studies can be used to predict the severity of fetal anaemia. This may lead to a reduction of invasive diagnostic tests, to more accurate timing of intrauterine transfusions, and thus to a higher survival rate.