President, The American College of Obstetricians and Gynecologists
Because women expect to gain weight while they are pregnant, some think of pregnancy as a time when it’s okay to indulge all cravings and add on pounds with abandon. But how much weight you put on does make a difference, and gaining too much can cause both short- and long-term health consequences for you and your baby.
Excess weight gain during pregnancy increases the risk of conditions such as preeclampsia (high blood pressure during pregnancy) and gestational diabetes, especially in women who are overweight or obese at the start of pregnancy. It can also raise the risk of cesarean delivery.
In the long term, the more weight you gain while you’re pregnant, the more you have to lose after the baby is born, and the more likely that the extra weight will become permanent. This retained pregnancy weight can contribute to a higher future risk of heart disease, diabetes, and other health problems.
So how much is too much? Pregnancy weight gain guidelines are based on a woman’s pre-pregnancy body mass index (BMI) – a measurement of body fat in relation to height and weight. Before a woman becomes pregnant, her physician can calculate her BMI to determine whether she is underweight (BMI less than 18.5); normal weight (BMI from 18.5-24.9); overweight (BMI of 25.0-29.9); or obese (BMI 30 or greater). For example, a 5’5” woman who weighs 132 pounds is within the normal range with a BMI of 22.
ACOG recommends that underweight women gain 28-40 pounds during pregnancy; normal weight women gain 25-35 pounds; overweight women gain 15-25 pounds; and obese women gain between 11-20 pounds. Unfortunately, an estimated 40-73 percent of women gain weight outside of those ranges.
Gradually gaining weight through a moderate increase in calories is key. Normal-weight women should aim to add 100-300 calories to their pre-pregnancy food intake each day–about the equivalent of a peanut butter and jelly sandwich with a glass of milk.
Under-weight women should consume slightly more and overweight women should consume slightly less. To ensure that you’re getting the right nutrients, try to replace empty calories in your diet with healthier choices such as whole grains, lots of fruits and vegetables, healthy fats, dairy, lean meats and fish, and beans.
Talk to your doctor about getting to or maintaining a healthy weight before you get pregnant, whether you are actively trying to have a baby or not. He or she can suggest weight loss or maintenance strategies to help you avoid the negative effects of excess weight on you, your baby and your pregnancy.