
Pregnancy Weight Gain Calculator
Estimates a schedule for healthy weight gain based on guidelines from the Institute of Medicine
Recommended Weight Gain
Your Pre-pregnancy BMI
Your Current Status
About Pregnancy Weight Gain
Pregnancy can lead to significant changes to women's bodies and daily routines. One such change is weight gain to ensure that there are enough nutrients for the development of the fetus as well as to store enough nutrients in preparation for breastfeeding. While weight gain during pregnancy is normal and necessary, studies have shown that certain ranges of weight gain given a specific body mass index (BMI) result in more positive outcomes for both fetus and mother.
Generally, it is recommended that pregnant women gain only 1-4 pounds during the first 3 months of pregnancy, and 1 pound per week during the remainder of the pregnancy. It is possible to achieve 1 pound per week by consuming an additional ~300 calories per day, which is roughly equivalent to eating an extra sandwich plus a glass of milk or a baked potato plus 2 ounces of meat plus an apple.
Recommendations for Total Weight Gain
Prepregnancy BMI (kg/m²) | Category | Total Weight Gain Range | Total Weight Gain Range for Twins |
---|---|---|---|
<18.5 | Underweight | 28-40 lbs | - |
18.5-24.9 | Normal Weight | 25-35 lbs | 37-54 lbs |
25.0-29.9 | Overweight | 15-25 lbs | 31-50 lbs |
>30.0 | Obese | 11-20 lbs | 25-42 lbs |
Pregnancy Weight Gain Distribution
Component | Weight |
---|---|
Enlarged breasts | 1-3 pounds |
Enlarged uterus | 2 pounds |
Placenta | 1.5 pounds |
Amniotic fluid | 2 pounds |
Increased blood volume | 3-4 pounds |
Increased fluid volume | 2-3 pounds |
Fat stores | 6-8 pounds |
Potential Complications
There are adverse effects for either insufficient or excessive weight gain during pregnancy. Insufficient weight gain can compromise the health of the fetus and cause preterm, or premature birth; excessive weight gain can cause labor complications, giving birth to significantly larger than average fetuses, postpartum weight retention, as well as increase the risk of requiring a cesarean section (C-section).