Determining Amino Acid Requirements in Pregnant Women

Phenylalanine and tyrosine are aromatic amino acids that people need to obtain in their diets. Amino acids are the building blocks for protein, are are therefore required to form tissues in the body. It is well known that pregnant women require more protein in their diets, but the exact amount for each amino acid is undetermined. To find out how much of phenylalanine and tyrosine pregnant women require, the investigators plan to study pregnant women in early and late gestation with a modern minimally invasive technique.