Haematological Values in Cord Blood in Relation to Fetal Hypoxia

Abstract

Summary Haematological values in cord venous blood were studied in 458 newborn infants born at term. The severity of hypoxia in these babies was determined by measuring the pH in cord venous blood, and in cord arterial blood. Hypoxia was associated with increases in haemoglobin, in the red cell count, in the white cell count and in the haematocrit. Furthermore, the increase in the mean corpuscular volume, and decrease in mean corpuscular haemoglobin concentration could have been due to a net influx of less mature red cells into the circulation. It is suggested that fetal erythropoiesis is stimulated by intrapartum hypoxia.

A study on the measurement of the nucleated red blood cell (nRBC) count based on birth weight and its correlation with perinatal prognosis in infants with very low birth weights

“…Previous studies have reported the correlation of neonatal asphyxia and nRBC count4, 27, 28), and the correlation is likely to be attributable to the mechanism in which asphyxia, upon delivery, transfers blood from the intrauterine placenta to a fetus29), and the circulatory blood increases due to the increased blood influx into the placenta30), leading to an increase in the nRBC count due to the influx of premature red blood cells into the circulation along with the increased blood volume17). It is more difficult, however, to evaluate neonatal asphyxia in premature infants than in full-term infants20), and the gestational age affects the Apgar score in premature infants19).…”

“…The nRBC count was described per 100 WBC through the Wright stain of the blood smear, and was then converted into the absolute count over the corrected WBC count to calculate the absolute nRBC count. The corrected WBC count and the absolute nRBC count were calculated as follows17):…”

Nucleated red blood cells in human fetal scalp capillary blood samples: a feasibility study

“…Georgieff and associates used a fetal sheep model to document significant reticulocytosis following acute or chronic hypoxia, or erythropoietin administration 27 . Similarly, D'Souza and colleagues suggested that intrapartum fetal hypoxia stimulated erythropoiesis, with mobilization of both white blood cells and immature erythrocytes into the peripheral circulation 28 . Snijders and co-workers demonstrated that erythropoietin production in response to tissue hypoxia occurred as early as 26 weeks' gestation with measurable physiological effects on erythropoiesis 29 .…”

Umbilical Cord Blood Rheology in Relation to Maternal Disease and Fetal Hypoxia

“…All MEA values, how ever, are markedly lower than those ob served in pregnant women [8], placental district via vasoconstriction of the regional vessels and increased resistance. In fact, the placental blood volume is reduced in intrapartum hypoxia [11,12] and hemo globin, hematocrit and mean corpuscular volume were found to be increased in the cord blood of neonates who suffered from intrapartum hypoxia [ 13]. Also the detection of immature cells suggests that fetal erythropoiesis may be stimulated by hypoxia and may contribute to an increased fetal blood volume [14].…”