There will be randomized sequential assignment of pregnant women at the initial clinic visit to Diet A, a high proportion of calories from refined grains as a carbohydrate source, and Diet B, a high proportion of calories from whole grains. Random number assignment is impractical for counseling purposes and blinding not possible. Therefore, randomization by diet assignment by day of initial visit via random number was chosen. If the random number is odd Diet A would be selected, if the random number is even Diet B will be selected for that day.
