Pregnancy Weight Gain Calculator
以下详细说明暂以英文提供。
How the recommendations work
Gain guidance starts from your body mass index just before pregnancy, not your weight during it. Someone starting underweight is encouraged to gain more; someone starting with obesity is encouraged to gain less. Only a small share of the total is the baby itself — the rest is placenta, fluid, blood volume, and tissue that supports recovery and breastfeeding. The weekly pace in the second and third trimesters matters more than any single weigh-in.
If your gain is off the range
Weight gain rarely follows a smooth line, and a stretch above or below the band is common with morning sickness, fluid shifts, or activity changes. What helps is steady nutrition — protein, iron, folate, and enough calories — plus walking or swimming as tolerated. Large, persistent deviations deserve a conversation with your prenatal provider, who can check growth and screen for conditions such as gestational diabetes. This tool is informational, not medical advice.
常见问题
Do I really need to gain weight in the first trimester?
Only a little — roughly 1–4 lb (0.5–2 kg) total, and sometimes less with nausea. The calculator ramps its suggested range gradually across the first 13 weeks for that reason. Your provider cares most about the overall pattern, not early ounces.
Are the twin ranges the same for every BMI?
No. Twin guidance is higher across the board — for example 37–54 lb when starting underweight versus 25–37 lb with obesity — and doctors monitor twin growth more intensively. Select the twins option to see the matching range.