Gestational Weight Gain

IOM 2009 recommendations by pre-pregnancy BMI. Computes expected range at the current gestational age and flags actual gain as on-track, below, or above recommendation.

Reviewed by Pooja V. Menon, Registered Dietitian · Last updated Apr 26, 2026

Inputs are saved in your browser only — clear them any time from the Tools index.

Pre-pregnancy BMI (kg/m²)

Pregnancy type

Gestational age (weeks)

IOM 2009 recommendations

Pre-pregnancy BMI	Total gain (singleton)	Rate 2nd / 3rd trimester	Total gain (twins, provisional)
Underweight (< 18.5)	12.5 – 18 kg	0.44 – 0.58 kg/wk	insufficient data
Normal (18.5 – 24.9)	11.5 – 16 kg	0.35 – 0.50 kg/wk	17 – 25 kg
Overweight (25 – 29.9)	7 – 11.5 kg	0.23 – 0.33 kg/wk	14 – 23 kg
Obese (≥ 30)	5 – 9 kg	0.17 – 0.27 kg/wk	11 – 19 kg

First-trimester gain of roughly 0.5–2 kg is assumed across all groups; the per-week rate applies from week 14 onward.

Indian context (NIN-DGI 2024)

ICMR-NIN's Dietary Guidelines for Indians 2024 aligns with IOM 2009 on the broad principle that pre-pregnancy BMI should drive the gain target, but uses Asian-population BMI cut-offs (overweight ≥ 23, obese ≥ 27.5) rather than WHO Standard. For an Indian woman, applying the Asian cut-off — and pairing the gain target with NIN's + 350 kcal (2nd trimester) / + 600 kcal (3rd trimester) energy increment — is generally more appropriate than IOM 2009 alone. NIN-DGI also reiterates the role of an iron–folic acid (IFA) tablet, calcium, and iodised salt across pregnancy and lactation.

Sources

Institute of Medicine (US) and National Research Council. Weight Gain During Pregnancy: Reexamining the Guidelines. Washington DC: National Academies Press, 2009.
ACOG Committee Opinion No. 548. Weight Gain During Pregnancy. Obstet Gynecol 2013;121:210–2 (reaffirmed 2020).
ICMR-NIN. Dietary Guidelines for Indians 2024, Guideline 2 (Pregnancy and lactation), p.13–17.