Gaining Weight for Three

10.05.11 When you're expecting twins, adding pounds earlier is a good thing.

In the past, most women who were pregnant with twins were advised to gain 35 pounds to  45 pounds, regardless of their prepregnancy size. But more recent guidelines from the Institute of Medicine are individualized to give twins a greater chance to be born healthy to a healthy mother.

"The newer weight-gain guidelines are tailored to your prepregnancy body mass index [BMI]," says Susanne Tout, R.D., L.D., IBCLC, clinical program coordinator and dietitian at the Texas Children's Hospital Fetal Center Program for Multiples in Houston.

Also important is seeing consistent weight gain throughout pregnancy, specifically before 28 weeks; this significantly decreases prematurity, increases birth weights and reduces newborn mortality. If you prepregnancy BMI was normal (18.5 to 24.9), experts now recommend gaining 37 pounds to 54 pounds; 20 to 30 pounds by 20 weeks; and 30 to 46 pounds by 28 weeks and the rest in the last trimester. Other recommendations for women pregnant with twins:

• OVERWEIGHT (BMI 25 to 29.9) Gain 31 to 50 pounds

• OBESE (BMI 30-plus) Gain 25 to 42 pounds 

• UNDERWEIGHT (BMI <18.5) Because of insufficient data, no guidelines are available.

Do you ever wonder where you pregnancy pounds go? Click over to our weight gain chart to see a breakdown. Plus, check out our food tips for ways to keep your pregnancy weight gain within reason. —Jeanne Faulker, R.N.