Maintaining a healthy weight before pregnancy and gaining a healthy amount of weight during pregnancy is important. Living a healthy lifestyle helps the baby to grow and develop and also helps create a more positive pregnancy and birthing experience for the mother. On the other hand, the risk of a baby being born with a birth defect increases slightly when their mother is obese. You have probably heard the saying “eating for two” while pregnant, however, that is an exaggeration of how much a pregnant woman should be eating. A healthy woman should try to consume 300 calories more per day to have a healthy weight gain during pregnancy. Healthy weight gain is dependent on a woman’s weight before getting pregnant. Healthy women should aim to gain 2 to 4 pounds during the first trimester and then a pound every additional week for a total of 25 to 35 pounds. Underweight women need to gain more weight during pregnancy, around 28 to 40 pounds, and overweight women need to gain less, around 15 to 25 pounds.