Calculate recommended weight gain during pregnancy based on pre-pregnancy BMI. Track healthy pregnancy weight.
Track healthy weight gain during pregnancy.
The Pregnancy Weight Gain Calculator helps expectant mothers track healthy weight gain throughout pregnancy. Based on guidelines from the American College of Obstetricians and Gynecologists (ACOG) and the Institute of Medicine (IOM), this calculator provides personalized recommendations based on your pre-pregnancy BMI, ensuring optimal outcomes for both mother and baby.
Weight gain during pregnancy is not just about "eating for two"—it's about providing the right nutrients for your baby's development while maintaining your own health. The weight gained includes the baby (7-8 lbs), placenta (1.5 lbs), amniotic fluid (2 lbs), increased blood volume (4 lbs), breast tissue (2 lbs), uterus (2 lbs), and fat stores for breastfeeding (7-8 lbs). Gaining too little can lead to low birth weight, while gaining too much increases risks of gestational diabetes, high blood pressure, and delivery complications.
Weight gain isn't linear throughout pregnancy. Most women gain little in the first trimester (1-4 lbs total), with the majority of weight gained in the second and third trimesters (about 1 lb per week for normal-weight women). Your healthcare provider will monitor your weight at each prenatal visit and can provide personalized guidance.
Weekly rate: 1 lb (underweight), 1 lb (normal), 0.6 lb (overweight), 0.5 lb (obese).
| Pre-pregnancy BMI | Category | Total Gain (lbs) | Weekly (2nd/3rd) |
|---|---|---|---|
| <18.5 | Underweight | 28-40 | 1 lb/week |
| 18.5-24.9 | Normal | 25-35 | 1 lb/week |
| 25-29.9 | Overweight | 15-25 | 0.6 lb/week |
| ≥30 | Obese | 11-20 | 0.5 lb/week |
A woman with normal pre-pregnancy BMI of 22 at week 24: Expected gain = 3 lbs (first tri) + 12 weeks × 1 lb = 15 lbs. Her target range is 25-35 lbs total, so she's on track.
Related tools: BMI Calculator to determine your category, Due Date Calculator to track your timeline, and Calorie Calculator for nutritional planning.
Based on pre-pregnancy BMI. Normal BMI: gain 25-35 lbs total. Overweight: 15-25 lbs. Underweight: 28-40 lbs. Gain ~1 lb/week in 2nd-3rd trimester.
Normal BMI: 25-35 lbs. This includes baby (7-8 lbs), placenta, fluid, blood volume, breast tissue, and fat stores. More or less based on starting BMI.
Yes, first trimester gain is typically only 1-4 lbs total. Morning sickness may even cause weight loss. Most gain happens in 2nd and 3rd trimesters.