CheckBodyScore
Pregnancy Weight Gain Calculator
Recommended Healthy Weight Gain
IOM Guidelines
The goal is based on the Institute of Medicine (IOM) guidelines for singleton and twin pregnancies.
Tracking Healthy Pregnancy Weight Gain
The **Pregnancy Weight Gain Calculator** is an essential tool for monitoring maternal health, providing a recommended **healthy weight gain** range based on your **pre-pregnancy BMI** and whether you are carrying twins. Following these **IOM guidelines** (Institute of Medicine) helps optimize the health of both the mother and the baby and minimizes risks associated with excessive or inadequate **total pregnancy weight gain**.
Weight Gain Guidelines by Pre-Pregnancy BMI
The **healthy weight gain** targets vary significantly depending on the mother's starting weight class. All targets are provided in pounds (lbs) and apply to singleton pregnancies unless noted:
| BMI Category | Recommended Gain (lbs) | Weekly Gain (lbs) |
|---|---|---|
| Underweight ($<18.5$) | 28 – 40 lbs | 1.0 - 1.3 |
| Normal Weight ($18.5-24.9$) | 25 – 35 lbs | 0.8 - 1.0 |
| Overweight ($25.0-29.9$) | 15 – 25 lbs | 0.5 - 0.7 |
| Obese ($\geq 30.0$) | 11 – 20 lbs | 0.4 - 0.6 |
The calculator first determines your **pre-pregnancy BMI** and then provides your personalized **total pregnancy weight gain** range, along with the ideal rate for the second and third trimesters.
Twin Pregnancy Goals
**Twin pregnancy** requires higher weight gain to support multiple babies. The **IOM guidelines** adjust the **healthy weight gain** target upwards, typically recommending $37$ to $54$ lbs for normal BMI starting weight. Consult your physician immediately for specific advice if you are expecting multiples.
Pregnancy Weight Gain FAQs
Your **pre-pregnancy BMI** is calculated using your height and your weight immediately before becoming pregnant. This factor is the basis for determining your recommended **healthy weight gain** range, according to **IOM guidelines**.
Mothers who are **overweight** or **obese** before pregnancy already have adequate energy reserves. Therefore, the recommended **total pregnancy weight gain** is lower to minimize risks like gestational diabetes and preeclampsia, following **IOM guidelines**.
Weight gain in the first trimester is generally minimal, typically only $1$ to $4$ lbs, regardless of your **pre-pregnancy BMI**. The majority of the **healthy weight gain** occurs during the second and third trimesters.