Zinc and alkaline phosphatase were examined in 41 pregnant women (gestational weeks 35-41) and in 12 women within 24 h of delivery. The serum-zinc level was reduced in all the women, though to a lesser degree in women giving birth to small for gestational age (SGA) babies than in the control mothers. The difference between the two groups was significant (p = 0.019). Erythrocyte-zinc increased during pregnancy, more in control mothers than in SGA mothers (p = 0.020). Granulocyte-zinc was not significantly reduced in pregnancy and no difference was found between SGA mothers and control mothers. Alkaline phosphatase levels in serum and granulocytes were elevated equally in the two groups. These findings show that zinc level changes occur in pregnancy, but that the changes do not appear to be a dominant cause of SGA pregnancy, in Danish women.