See the recommended weight gain for your pregnancy.
It depends on your weight before pregnancy. With a normal BMI (18.5–24.9) the Institute of Medicine suggests 11.5–16 kg across a single pregnancy — about 0.35–0.5 kg a week after the first trimester.
Healthy weight gain in pregnancy supports your baby's growth and your own health. This calculator works out your pre-pregnancy BMI and shows the Institute of Medicine (IOM) recommended total gain for one baby or twins, the weekly rate after the first trimester and an approximate expected gain by week. Enter your current week and weight to compare.
These are population guides: your doctor or midwife will tailor them to you. Pregnancy is not a time to diet; if you are worried about your weight, talk to your care team. Also see the Pregnancy Calculator, the BMI Calculator and the Protein Calculator (pregnancy option).
The calculator applies the standard published formulas step by step.
| Item | Value |
|---|---|
| Pre-pregnancy BMI | 22 — Normal weight (BMI 18.5–24.9) |
| Recommended total gain | 11.5–16 kg (25–35 lb) |
| Gain in the first trimester | 0.5–2 kg in total |
| Weekly gain from week 14 on | 0.35–0.5 kg a week (0.8–1.1 lb) |
| Expected gain by week 28 | 5.8–9.5 kg |
| Your gain so far | 8 kg |
| Compared with the guide | Within the usual range |
| Week | Expected gain | Expected weight |
|---|---|---|
| Week 8 | 0.3–1.2 kg | 60.3–61.2 kg |
| Week 13 | 0.5–2 kg | 60.5–62 kg |
| Week 20 | 3–5.5 kg | 63–65.5 kg |
| Week 24 | 4.4–7.5 kg | 64.4–67.5 kg |
| Week 28 | 5.8–9.5 kg | 65.8–69.5 kg |
| Week 32 | 7.2–11.5 kg | 67.2–71.5 kg |
| Week 36 | 8.6–13.5 kg | 68.6–73.5 kg |
| Week 40 | 10–15.5 kg | 70–75.5 kg |
| Case | Total gain |
|---|---|
| Before pregnancy 48 kg | 12.5–18 kg |
| Before pregnancy 60 kg | 11.5–16 kg |
| Before pregnancy 72 kg | 7–11.5 kg |
| Before pregnancy 90 kg | 5–9 kg |
| 60 kg, twins | 16.8–24.5 kg |
With a normal BMI, 11.5–16 kg (25–35 lb) for one baby. Recommendations are higher if you were underweight and lower if you were overweight.
For a normal BMI, about 16.8–24.5 kg (37–54 lb). Your doctor will set a personal target.
About 0.5–2 kg in the first trimester, then roughly 0.35–0.5 kg a week for a normal BMI in the second and third.
Mention it at your next antenatal visit. Rates vary and what matters is the trend and your baby's growth.
No. Eat a balanced diet with enough calories and nutrients, and ask your care team for personal advice.
Many Indian clinicians use the IOM ranges with WHO BMI categories, though some adapt them for Asian BMI cut-offs. Follow your doctor's guidance.
It uses the published formula: BMI = pre-pregnancy weight ÷ height² expected gain = 0.5–2 kg + weekly rate × (week − 13) The full method and a worked example are shown on this page.
No. The calculator gives general estimates for information and education. It cannot diagnose or treat anything, so please speak to a doctor or qualified professional about your own health.
Yes. Choose centimetres or feet and inches for height, and kilograms, pounds or stone for weight; the results are converted for you.
No. Everything is calculated in your browser and nothing you enter is uploaded or saved.
