ACOG gestational weight guidelines in the United States
ACOG strongly endorses the Institute of Medicine (IOM) gestational weight gain recommendations to optimize perinatal outcomes for both mother and infant.
Excessive gestational weight gain increases risks of gestational diabetes, preeclampsia, cesarean delivery, and infant macrosomia (birthweight >4,000 g).
Conversely, inadequate weight gain is linked to preterm birth and small-for-gestational-age (SGA) infants. ACOG encourages tracking weekly gain in the second and third trimesters.
Worked example: US weight trajectory
A woman with pre-pregnancy weight of 140 lbs and height of 5 ft 5 in (BMI 23.3) is at 28 weeks.
Expected gain at 28 weeks is 16 to 22 lbs. An actual gain of 19 lbs is perfectly on track within the 25–35 lb total target.
US weight inputs
Pre-pregnancy Weight
Weight in pounds prior to conception.
CALCULATOR QUESTIONS
ACOG / IOM pregnancy weight gain calculator questions
How much weight should I gain if carrying twins?
For normal pre-pregnancy BMI, IOM guidelines recommend a total gain of 37 to 54 lbs for twins. For overweight BMI, 31 to 50 lbs, and for obese BMI, 25 to 42 lbs.
How quickly should weight be gained in the second trimester?
For a normal BMI singleton pregnancy, the target rate is approximately 0.8 to 1.0 lb per week (about 4 lbs per month).