Amniotic fluid copper and zinc concentrations in human pregnancy.

Amniotic fluid concentrations of zinc and copper were measured in human pregnancy of 12 to 44 weeks' gestation. Although mean values for both metals are relatively flat throughout pregnancy, there appears to be a relative increase in copper levels between 26 and 33 weeks' gestation, and increasing levels of zinc after 34 weeks. Correlations with fetal age or fetal-maternal disease are not apparent in specimens from this heterogenous population.