Elevated count of nucleated red blood cells (n-RBCs) in the cord blood of fetuses at birth as well as prolongation of pregnancy, have been suggested as predictor of adverse perinatal outcome.
A prospective cohort study to evaluate the association between umbilical cord nucleated RBCs (uc-nRBC) count in uncomplicated overdue pregnancies with their neonatal outcome.
PATIENTS & METHODS:
One hundred and eighty five ladies with overdue pregnancy (41-42 weeks+3days) were included in the study. Dating was confirmed by their precisely recalled last menstrual periods and early pregnancy sonographies. At their deliveries, umbilical cord nucleated red blood cells were counted and expressed per 100 white blood cells. Mode of delivery, the newborn outcome and the risk factors were all analyzed with the obtained counts of the n-RBCs using descriptive and inferential statistics.
The number of n-RBCs counted, ranged from 3-43/ 100 WBC and accordingly the cases were categorized into 3 groups. Those with more than 20 n-RBC/100 WBC (high risk group) showed higher incidence of neonatal risk outcomes (49.3% of the calculated total risks) than the group with 3-10 n-RBC (low risk group) which included about half of the participants, it exhibited only 20.5% of the total risks. The risk outcomes include; meconium staining, admission to neonatal intensive care unit, neonatal death and Apgar score at 7 minutes less than 5. Moreover, cesarean section rate in high risk group was almost double its rate in the low risk group (44.7% Vs 22.5%).The association between risk outcome and n-RBC counts is statistically highly significant P value < 0.001.
In overdue pregnancy, umbilical cord n-RBC count of the new born is significantly associated with risk outcome.