Plasma zinc and copper levels in maternal, placental intervillous space and cord blood

Abstract

Zinc and copper levels in maternal, placental intervillous space (PIS) and cord blood from 82 parturients and infants were studied. Immediately after expulsion, blood samples from the maternal radial vein, PIS and umbilical cord artery and vein were collected for zinc and copper analysis. Maternal zinc values (72.3±18.2 ug/dl) were significantly lower (p<0.01) than PIS and newborn values. PIS zinc concentration (100.7±26.7 ug/dl) was the same as that of newborn blood, i.e. 104.4±20.1 ug/dl in the cord vein and 103.7±24.05 ug/dl in the cord artery. No difference in zinc levels was found between the cord artery and vein. Maternal copper values (194.8±41.0 ug/dl) were equal to PIS and higher than newborn copper levels (p<0.01). PIS copper concentration (180.9±38.9, ug/dl) was higher than that of newborn blood, i.e. 46.6±18.5 ug/dl in the cord vein and 46.4±21.0 ug/dl in the cord artery. No difference in copper levels was found between the cord artery and vein. A correlation was found between maternal and PIS zinc levels and cord artery and vein zinc levels. Maternal and cord vein, maternal and cord artery, PIS and cord vein and PIS and cord artery zinc concentrations showed no significant correlation. The same was found regarding copper levels. The data suggest that zinc and copper transport could be more dependent on the carrier capacity of the fetal plasma transport system than the maternal or PIS zinc levels.