Pregnancy weight gain charts guide optimal fetal growth, maternal health, and delivery outcomes based on your pre-pregnancy BMI. Standard recommendations suggest 25-35 lbs total for normal BMI (18.5-24.9), with tailored ranges for underweight (28-40 lbs), overweight (15-25 lbs), and obese (11-20 lbs) categories. Steady gains—minimal first trimester, 0.5-1 lb/week later—reduce risks like preterm birth or C-sections. Use our Pregnancy Weight Gain Calculator to generate your custom chart by entering BMI, starting weight, current week, and multiples status for visual progress tracking and alerts.
Pre-Pregnancy BMI Categories and Total Gain Targets
Calculate BMI (weight in kg ÷ height in m²) before pregnancy to find your range. These IOM-based guidelines apply to singleton pregnancies:
| BMI Category | BMI Range | Total Recommended Gain | Twins Adjustment |
|---|---|---|---|
| Underweight | <18.5 | 28-40 lbs | 50-62 lbs |
| Normal | 18.5-24.9 | 25-35 lbs | 37-54 lbs |
| Overweight | 25-29.9 | 15-25 lbs | 31-50 lbs |
| Obese | ≥30 | 11-20 lbs | 25-42 lbs |
Detailed Weight Gain Chart by Trimester and BMI
Expect 1-4 lbs in trimester 1, then consistent weekly gains. Here’s your trimester-by-trimester breakdown:
Normal BMI (18.5-24.9): 25-35 lbs Total
| Trimester | Weeks | Weekly Rate | Expected Gain | Cumulative |
|---|---|---|---|---|
| First | 1-13 | 0.2-0.3 lbs | 1-4 lbs | 1-4 lbs |
| Second | 14-27 | 1 lb | 12-14 lbs | 13-18 lbs |
| Third | 28-40 | 1 lb | 11-13 lbs | 25-35 lbs |
Underweight BMI (<18.5): 28-40 lbs Total
| Trimester | Weeks | Weekly Rate | Expected Gain | Cumulative |
|---|---|---|---|---|
| First | 1-13 | 0.3-0.4 lbs | 2-5 lbs | 2-5 lbs |
| Second | 14-27 | 1.2-1.5 lbs | 14-18 lbs | 16-23 lbs |
| Third | 28-40 | 1.2-1.5 lbs | 12-17 lbs | 28-40 lbs |
Overweight BMI (25-29.9): 15-25 lbs Total
| Trimester | Weeks | Weekly Rate | Expected Gain | Cumulative |
|---|---|---|---|---|
| First | 1-13 | 0-0.3 lbs | 0-4 lbs | 0-4 lbs |
| Second | 14-27 | 0.5-0.7 lbs | 6-10 lbs | 6-14 lbs |
| Third | 28-40 | 0.5-0.7 lbs | 9-11 lbs | 15-25 lbs |
Obese BMI (≥30): 11-20 lbs Total
| Trimester | Weeks | Weekly Rate | Expected Gain | Cumulative |
|---|---|---|---|---|
| First | 1-13 | 0-0.2 lbs | 0-3 lbs | 0-3 lbs |
| Second | 14-27 | 0.4-0.5 lbs | 5-7 lbs | 5-10 lbs |
| Third | 28-40 | 0.4-0.5 lbs | 6-10 lbs | 11-20 lbs |
Note: First trimester includes nausea-related fluctuations; focus on nutrition over scale.
Weekly Pregnancy Weight Gain Progress Tracker
Print or log this for home monitoring (Normal BMI example—adjust via calculator):
| Gestational Week | Target Min (lbs) | Target Max (lbs) | Your Weight | Notes |
|---|---|---|---|---|
| 12 | 1 | 4 | ||
| 20 | 8 | 12 | ||
| 28 | 14 | 20 | ||
| 36 | 21 | 28 | ||
| 40 | 25 | 35 |
Input your data into Pregnancy Weight Gain Calculator for auto-filled, printable charts.
Where Your Weight Gain Distribution Goes
- Baby: 7-8 lbs
- Placenta/Fluid: 4-5 lbs
- Blood/Breasts/Uterus: 11-14 lbs
- Maternal Fat Stores: 5-9 lbs (breastfeeding fuel)
Calorie Needs by Trimester for Healthy Gain
| Trimester | Extra Calories/Day | Example Additions |
|---|---|---|
| First | 0 (1,800 total) | Nutrient-dense meals |
| Second | +340 (2,200 total) | Yogurt + nuts + fruit |
| Third | +450 (2,400 total) | Salmon + quinoa + veggies |
Benefits of Staying in Your BMI Range
- Reduced gestational diabetes (20-30% lower risk)
- Lower C-section rates
- Healthier birth weights (5.5-8.8 lbs ideal)
- Easier postpartum recovery
Red Flags and When to Adjust
- Too Slow: <0.3 lb/week after trimester 1 → Add protein-rich snacks.
- Too Fast: >2 lbs/week → Cut sugars, increase walking.
- Sudden changes? Discuss at prenatal visits.
Quick Start: Generate Your Chart
- Calculate pre-pregnancy BMI.
- Enter into Pregnancy Weight Gain Calculator.
- Get trimester tables, weekly goals, and nutrition plans.
- Weigh weekly (same time/conditions).
FAQs: Pregnancy Weight Gain Charts
Q: BMI changed? Recalculate if significant pre-pregnancy shift.
Q: Twins chart? Calculator auto-adjusts.
Q: Vegan gains? Same targets; emphasize plant proteins/DHA.
Create Your Custom Pregnancy Weight Gain Chart Today
Enter your details in our Pregnancy Weight Gain Calculator for instant, downloadable charts tailored to your BMI, trimester, and needs. Share your starting BMI below for specific advice!
Stay on track for a healthy pregnancy and baby—your chart awaits.