Nucleated red blood cells as a marker in acute and chronic fetal asphyxia

OBJECTIVE: To investigate the variations of nucleated red blood cell (NRBC) counts in acute and chronic fetal hypoxia and to examine if it could be possible to establish a cutoff value for the number of NRBCs for prediction of fetal acidosis. METHOD: We prospectively studied 77 pregnant women. Patients were grouped as acute (n=11) and chronic fetal distress (n=21) and controls (n=45). At delivery the umbilical cord was double clamped and blood samples were collected. RESULTS: The mean NRBC counts in chronic fetal distress group was higher than acute fetal distress. NRBC counts were found to be correlated with umbilical cord pH (r=-0.57; P<0.001). The cutoff value predicting fetal acidosis was determined as 14/100 leukocytes (sensitivity 87%, specificity 81%) by using ROC analysis. CONCLUSION: The duration and the severity of fetal asphyxia may be predicted by the number of NRBCs per leukocyte.