ACT Nutrition Support Service » Weight gain during pregnancy

Weight gain during pregnancy

ACT Nutrition Support Service » Weight gain during pregnancy

Weight gain during pregnancy

As your baby grows, you will gradually gain weight. How much weight you gain during pregnancy largely depends on your pre-pregnancy weight.

What is a healthy weight gain for me?

The amount of weight gain considered appropriate during pregnancy depends on what your pre-pregnancy Body Mass Index (BMI) was.

What is BMI?

The BMI is a weight for height calculation that is used to categorise adults into classes of underweight, healthy weight, overweight and obese. The calculation is performed by taking your weight (in kilograms) and dividing it by your height (in metres) squared.

To calculate your BMI, you can use one of the many available calculators online, or you can follow the steps below:

  1. Multiple your height in metres (m) by itself.

For example, 1.64m x 1.64m = 2.6896

  1. Divide your weight in kilograms (kg) by the result in step one.

For example, 56kg รท 2.6896 =21. The person in this example has a BMI of 21.

Use the following tables to identify the appropriate amount of weight gain that suits you.

Classification

Pre-pregnancy BMI

Appropriate amount of weight gain (kg)

Underweight

Below 18.5

12.5-18

Healthy weight

18.5-24.9

11.5-16

Overweight

25.0-29.9

7.0-11.5

Obese

Above 30

5.0-9.0

If you are pregnant with twins or triplets the following amount of weight gain is considered appropriate:

Pre-pregnancy BMI

Appropriate amount of weight gain (kg)

Below 18.5

Talk with your obstetrician/doctor

18.5-24.9

17-25

25.0-29.9

14-23

Above 30

11-19

If I am above a healthy weight range and become pregnant, should I try to lose weight?

No, the best time to lose weight is pre-pregnancy. If you are overweight and become pregnant, try to minimise your weight gain by focussing on healthy foods in appropriate portions, with regular exercise, rather than aiming for weight loss.