Recommended Pregnancy Weight Gain Charts (IOM)
The Institute of Medicine (IOM) and ACOG revised their recommendations with a simple goal: match healthy pregnancy weight gain to your pre-pregnancy BMI. It's not one-size-fits-all. These ranges give you the best shot at a safe pregnancy and make postpartum recovery easier.
For Singleton Pregnancies (One Baby)
| Pre-pregnancy BMI | Category | Total Gain (lbs) |
|---|---|---|
| Below 18.5 | Underweight | 28 – 40 lbs |
| 18.5 – 24.9 | Normal Weight | 25 – 35 lbs |
| 25.0 – 29.9 | Overweight | 15 – 25 lbs |
| 30.0 and above | Obese | 11 – 20 lbs |
For Twin Pregnancies
| Category | Total Recommended Gain (lbs) |
|---|---|
| Normal Weight | 37 – 54 lbs |
| Overweight | 31 – 50 lbs |
| Obese | 25 – 42 lbs |
*Data provided by the Institute of Medicine (IOM). Always consult your OB-GYN for personalized advice, especially for triplet+ pregnancies.
Where Does Pregnancy Weight Go?
Here's what most women don't realize: only about 7-8 pounds is actually the baby. The rest? That's your body building the infrastructure to support new life. Here's where a typical 30-pound gain goes:
The Baby
7.5 lbs
Just the baby
Support Tissues
Fluids & Blood
Maternal Stores
7.0 lbs
For breastfeeding and recovery
Pregnancy Weight Gain by Trimester
First Trimester (Weeks 1 – 13)
Expected Gain: 1 to 5 lbs total.
Don't stress if you're not gaining much, or if morning sickness is keeping your scale in place. This is totally normal. A small weight loss here is okay, just stay hydrated. Your baby's still tiny; your body isn't demanding extra fuel quite yet.
Second Trimester (Weeks 14 – 27)
Expected Gain: 0.5 to 1 lb per week.
Your appetite's back, and your baby's growing fast. You're looking at an extra 300-340 calories daily, such as a bowl of oatmeal and a banana. Weight gain should feel steady and predictable now. If the scale's jumping around, that's when to chat with your provider.
Third Trimester (Weeks 28 – Birth)
Expected Gain: 0.5 to 1 lb per week.
You'll need about 450 extra calories daily now. Most of this weight gain goes straight to your baby, who's packing on pounds to prepare for the outside world. The scale might plateau in your final weeks, and that's perfectly fine.
Risks of Too Much or Too Little Weight Gain in Pregnancy
Gaining Too Much
Common risks include:
- Gestational Diabetes
- Preeclampsia (High Blood Pressure)
- Macrosomia (Large Baby)
- Increased chance of C-section
- Difficulty losing weight postpartum
Gaining Too Little
Common risks include:
- Preterm birth (Premature delivery)
- Low birth weight (under 5 lbs 8 oz)
- Developmental delays
- Difficulty initiating breastfeeding