Find out how much weight you should gain during pregnancy based on your pre-pregnancy BMI and current gestational week, per IOM 2009 guidelines.
| Trimester | Period | Approx. Gain |
|---|---|---|
| 1st Trimester | Weeks 1–13 | 1–4.5 lb (0.5–2 kg) |
| 2nd Trimester | Weeks 14–26 | ~1 lb/week |
| 3rd Trimester | Weeks 27–40 | ~1 lb/week |
The Institute of Medicine (IOM) 2009 guidelines recommend different amounts of total weight gain depending on your pre-pregnancy Body Mass Index (BMI).
| Pre-pregnancy BMI | Single Baby (lb) | Twins (lb) |
|---|---|---|
| Underweight (< 18.5) | 28–40 lb | 50–62 lb |
| Normal (18.5–24.9) | 25–35 lb | 37–54 lb |
| Overweight (25–29.9) | 15–25 lb | 31–50 lb |
| Obese (≥ 30) | 11–20 lb | 25–42 lb |
Note: These are general recommendations. Always consult your healthcare provider for personalized guidance during pregnancy.