Nucleated red blood cells in healthy infants of women with gestational diabetes.

OBJECTIVE: To evaluate whether absolute nucleated red blood cell (RBC) counts are elevated in large-for-gestational-age (LGA) infants of women with gestational diabetes compared with appropriate-for-gestational-age (AGA) infants of women with or without gestational diabetes. METHODS: We compared absolute nucleated RBC counts during the first 12 hours of life in three groups of term, vaginally delivered infants, LGA infants of women with gestational diabetes (n = 20), AGA infants of women with gestational diabetes (n = 20), and AGA infants of nondiabetic women (n = 30). We excluded infants of women with hypertension, smoking, alcohol or drug abuse, and those with fetal heart rate abnormalities in labor, low Apgar scores, hemolysis, blood loss, or chromosomal anomalies. RESULTS: There were no significant differences among groups in gestational age, gravidity, parity, maternal analgesia, 1- and 5-minute Apgar scores, and lymphocyte counts. Corrected white blood cell counts and hematocrit were significantly higher in LGA infants of women with gestational diabetes than in the other groups. The median nucleated RBC count was significantly higher in LGA infants of women with gestational diabetes (0.56 x 10(9)/L, range 0-1.8 x 10(9)/L) than AGA infants of women with gestational diabetes (0.13 x 10(9)/L, range 0-0.65 x 10(9)/L) and controls (0.0005 x 10(9)/L, range 0-0.6 x 10(9)/L) (P < .001). Multiple regression analysis showed that absolute nucleated RBC count was significantly correlated with birth weight (or macrosomia) and maternal diabetic status (r2 = .25, P < .001 for the multiple regression, contribution of birth weight r2 = .19, and diabetes r2 = .06). CONCLUSION: At birth, term LGA infants born to women with gestational diabetes had higher absolute nucleated RBC counts compared with AGA infants born to women with gestational diabetes and controls.