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Pregnancy Weight Gain Calculator

Check recommended pregnancy weight gain for your starting BMI.

Pre-pregnancy stats
cm
kg
wk

Recommended total gain

11.5–16 kg

pre-pregnancy BMI 22.8

Typical gain by week 24

≈ 6.8 kg

Guideline

IOM, singleton pregnancy

Twins raise the ranges substantially. Your obstetric provider's guidance overrides any calculator.

Ranges keyed to starting BMI

The Institute of Medicine ranges scale inversely with pre-pregnancy BMI: 11.5–16 kg for a normal BMI, less when starting heavier. Most gain arrives after week 13 — roughly 0.4–0.5 kg weekly through the second and third trimesters.

Where the weight goes

A ~13 kg gain is mostly not fat: baby (~3.5), placenta and fluid (~1.5), blood volume (~1.5), breast and uterine tissue (~2), fluid (~2), and 2–4 kg of energy stores for breastfeeding. Steady tracking beats any single weigh-in.

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