Cord serum erythropoietin in 90 healthy newborn term infants: relationship to blood gases and iron status markers.

In this study, we examined the cord serum erythropoietin (EPO) level in newborn infants in relation to venous cord blood gases and iron status markers (cord serum ferritin, cord serum transferrin saturation). The subjects were 90 healthy newborn term infants with a normal birth and 90 healthy women with an uncomplicated pregnancy and delivery. Within 14-18 weeks of gestation, 47 prospective mothers, allocated at random, received tablets containing 66 mg ferrous iron daily, and 43 received a placebo. Serum EPO was measured in women prior to delivery. Serum EPO, serum ferritin and serum transferrin saturation were analyzed in cord blood from the newborn. Blood gases (PO2, PCO2 and standard HCO3, PH) were measured in venous cord blood and Apgar scores were recorded. The cord serum EPO level in the newborn was not significantly affected by the iron supplementation to the mothers. In the entire series, the geometric mean cord serum EPO was 36 U/I, (median 32 U/I, 5-95% 16-150, range 12-380). There was no correlation between cord serum EPO and APgar score, cord blood PO2, PCO2, standard HCO3 and pH. In the newborn of placebo-treated mothers, log cord serum EPO was inversely correlated with log cord serum ferritin (r = -0.54, P < 0.0002) and cord serum transferrin saturation (r = -0.39, P < 0.011), suggesting that iron deficiency may occur in this newborn group.