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Pregnancy: Healthy Weight Gain

Overview

During pregnancy, lots of women wonder about how their body will change and how much weight they will gain. Maybe this is something that you've been thinking about too.

Weight gain is healthy and normal when you're pregnant. And there's no fixed number of kilograms that you should be aiming for. Instead, there's a range of weight gain that's good for you and your baby.

Ask your doctor or midwife what your range is for healthy weight gain. It's based on your health, your pregnancy, and your weight before pregnancy.

If you're worried about weight gain during pregnancy, try not to focus too much on the numbers. Think more about having a healthy pregnancy by being active and feeding your baby with healthy foods.

Why does weight gain during pregnancy matter?

Gaining too much or too little weight raises some health risks for you and your baby.

Gaining too much weight when you're pregnant can raise your risk of having a large baby. If your newborn is 4.5 kg (10 lb) or larger, you may be more likely to have:

  • A long labour and birth.
  • Caesarean birth.
  • An injury to you or your baby during childbirth.
  • A poor supply of oxygen for your baby during labour.

Also, a newborn who is 4.5 kg (10 lb) or larger may become overweight or obese later in life. That could mean that he or she will have a higher risk of type 2 diabetes.

Gaining too much weight during pregnancy can also make it harder to lose that weight later on.

And if you are very overweight (obese) during pregnancy, you have greater risks for:

Gaining too little weight when you're pregnant raises your baby's risks for early birth, and for low birth weight and size. When this happens, a newborn is at greater risk for:

  • Illness in the first weeks of life.
  • Physical and mental disabilities.
  • Long-term health problems later in life.

What about dieting during pregnancy?

Pregnancy is not the time to diet. Your baby needs you to eat a wide variety of foods. Follow Canada's Food Guide and focus on eating a variety of vegetables and fruits, whole grain foods, and protein foods. Limit sugary and high-fat foods.

If you have morning sickness and lose weight during your first trimester, your baby is unlikely to be affected. Just be sure your doctor knows. Get help with nausea and vomiting, if needed.

How much weight gain is good for you and your baby?

Ideally, you will gain weight slowly over your whole pregnancy. If you stop gaining weight for more than 2 weeks, or if you gain weight faster than expected, talk to your doctor or midwife.

Women who are pregnant with one baby

Based on your weight before pregnancy, experts say it is generally best to gain about: footnote 1

  • 12.5 kg (28 lb) to 18 kg (40 lb) if you are underweight.
  • 11.5 kg (25 lb) to 16 kg (35 lb) if you are at a healthy weight.
  • 7 kg (15 lb) to 11.5 kg (25 lb) if you are overweight.
  • 5 kg (11 lb) to 9 kg (20 lb) if you are obese. In some cases, a doctor or midwife may recommend that a woman not gain any weight.

Women who are pregnant with twins

Based on your weight before pregnancy, experts say it is generally best to gain about:footnote 2

  • 17 kg (37 lb) to 25 kg (54 lb) if you are at a healthy weight.
  • 14 kg (31 lb) to 23 kg (50 lb) if you are overweight.
  • 11 kg (25 lb) to 19 kg (42 lb) if you are obese. In some cases, a doctor or midwife may recommend that a woman not gain any weight.

How much can you eat during pregnancy?

Although pregnant women often joke that they're "eating for two," you don't need to eat twice as much food.

In general, pregnant women in their second trimester need to eat about 340 extra calories a day. Women in their third trimester need to eat about 450 extra calories a day.footnote 3 You can get about 340 calories in a peanut butter sandwich. Having a cup of 1% milk with a peanut butter sandwich is about 450 calories.

How much you can eat depends on:

Work with your doctor, midwife, or a dietitian to help you plan healthy meals and the right amount of calories for you.

References

Citations

  1. Public Health Agency of Canada. (2021). Your guide to a healthy pregnancy. Government of Canada. https://www.canada.ca/en/public-health/services/health-promotion/healthy-pregnancy/healthy-pregnancy-guide.html. Accessed August 16, 2021.
  2. Health Canada (2009). Prenatal nutrition guidelines for health professionals: Gestational weight gain. Available online: http://www.hc-sc.gc.ca/fn-an/nutrition/prenatal/ewba-mbsa-eng.php.
  3. Kaiser LL, Campbell CG (2014). Practice paper: Nutrition and lifestyle for a healthy pregnancy outcome. Journal of the Academy of Nutrition and Dietetics, 114(7): 1099-1103. http://www.eatrightpro.org/resource/practice/position-and-practice-papers/practice-papers/practice-paper-nutrition-and-lifestyl…. Accessed November 16, 2017.

Credits

Current as of: November 9, 2022

Author: Healthwise Staff
Medical Review:
Sarah Marshall MD - Family Medicine
Anne C. Poinier MD - Internal Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Femi Olatunbosun MB, FRCSC - Obstetrics and Gynecology