Hemoglobin and hematocrit values of Saudi newborns in the high altitude of Abha, Saudi Arabia.

A study was designed to determine the red cell values (hemoglobin and hematocrit) of neonates born in the high altitude of Abha and to compare these values with known values of other lowland areas of Saudi Arabia. From the cord blood of 587 normal, appropriate for gestational age and term infants born in 1993 in Abha Maternity Hospital, the ranges of Hb and Hct were 130 to 240 g/L and 0.24 to 0.79 L/L respectively. The mean Hb was 187 g/L. There was no significant difference between the male and female values. Also, 17% of the infants in this study were polycythemic, while no polycythemia was recorded in these lowland areas, and only 2% to 4% in the general global newborn population. It was therefore revealed that Abha newborns had higher red cell values at birth when compared to other newborns in the low altitude areas of Riyadh and Jeddah (P <0.001). We postulate that the high altitude (2700 meters above sea level) of Abha, and therefore its relative hypoxia, has induced high red cell values in infants born in the city. This phenomenon therefore warrants the adoption of higher red cell reference values and not necessarily those already documented in other Saudi newborn populations.