Blood samples were obtained from 244 pregnant teen-agers upon their initial visit to the prenatal clinic. The subjects sampled represented young women at varying stages of gestation from the tenth to fortieth week of pregnancy. The plasma levels of the metals iron, zinc, copper, calcium, and magnesium were determined; as well as the plasma levels of vitamins A, C, and the total carotenes. These changes were not altered significantly when the individual values were expressed as a ratio to their individual hematocrit value as an expression of hemodilution effect during pregnancy. A product-moment correlation study at all the measurements divided by the hematocrit disclosed statistical interrelationships with a very significant level of probability between plasma levels of copper, magnesium, and calcium; as well as lower levels of confidence in the statistical relationships between other minerals and vitamins. © 1969.