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Pregnancy Weight Gain In the First Trimester

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How much weight should you gain in the first trimester of your pregnancy?  

Not very much.

Weight gain in your first three months should be minimal (0.5 to 2.0 kilograms or 1.1 to 4.4 pounds). If you lose or gain a significant amount of weight (more than five to 10 per cent of your pre-pregnancy weight), talk with your healthcare provider for support.

To maintain a healthy weight, stay active while you’re pregnant. Here’s some advice on exercising safely during pregnancy. You can also check with your healthcare provider about what’s safe for you.

What is a Body Mass Index (BMI)?

BMI can help you and your health care provider figure out how much weight you should gain during your pregnancy. You should not use a BMI calculator if you’re already pregnant or under the age of 18. If you’re already pregnant, you can enter your weight before you got pregnant to help figure out your pre-pregnancy BMI. To figure out your BMI, click here. 

Research studies in large groups of people have shown that the BMI can be classified into four ranges linked with health risk:

  • underweight (BMI less than 18.5)
  • normal weight (BMIs 18.5 to 24.9)
  • overweight (BMIs 25 to 29.9)
  • obese (BMI 30 and over)

Talk with your health care provider about your BMI to find out what a healthy weight gain is in your pregnancy.

Weight loss and dieting are not recommended during pregnancy. Focus on healthy eating and healthy foods, not your weight. For more information, talk with your healthcare provider or call 8-1-1 to speak to a dietitian at HealthLink BC.

Resources & Links:

HealthLink BC: Nutrition and Weight Gain During Pregnancy 
HealthLink BC: BMI

Last Updated: August 11, 2013