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Health & FitnessGenerated accuracy model review: 2026-05-06

Pregnancy Weight Gain accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • This calculator follows the official **Institute of Medicine (IOM)** guidelines: * **Underweight (BMI < 18.5):** Gain 28-40 lbs * **Normal (BMI 18.5-24.9):** Gain 25-35 lbs * **Overweight (BMI 25-29.9):** Gain 15-25 lbs * **Obese (BMI 30+):** Gain 11-20 lbs

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Height (ft): 5
  • Height (in): 4
  • Pre-Pregnancy Weight: 140 lbs
  • Twins?: No

Expected outputs

  • Pre-Pregnancy BMI: 24
  • Recommended Gain: 25 - 35 lbs
  • BMI Category: Normal Weight

Known limitations

  • This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
  • Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

  • Recommended ranges are based on pre-pregnancy BMI categories, with separate guidance applied for singleton and twin pregnancies.
  • Weight gain is expected to progress unevenly rather than increase by the exact same amount each week.
  • Personal medical history, multiple gestation, and clinician advice can override general-range guidance.

Unit handling

  • Height (ft) accepts numeric values.
  • Height (in) accepts numeric values.
  • Pre-Pregnancy Weight accepts values in lbs.
  • Twins? accepts Yes/No values.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current pregnancy-weight-gain-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Pregnancy Weight Gain.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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