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Weight Gain During Pregnancy

On average, a healthy amount of weight gain during pregnancy is 25-35 pounds (11.3-15.9 kilograms) for normal weight women. This is usually reached by gaining 1-4 pounds (0.4 to 1.8 kilograms) during the first trimester, and about 2-4 pounds (.9-1.8 kilograms) each month from 4 months until delivery.

Where does this weight come from? According to the Nemours Foundation, this is how a 30 pound (13.6 kilogram) pregnancy weight gain is typically distributed:

  • 7.5 pounds (3.4 kilograms): your baby’s weight
  • 1.5 pounds (.6 kilograms): the placenta
  • 2 pounds (.9 kilograms): enlargement of your uterus
  • 2 pounds (.9 kilograms): amniotic fluid surrounding your baby
  • 2 pounds (.9 kilograms): breast enlargement
  • 4 pounds (1.8 kilograms): your extra blood
  • 7 pounds (3.17 kilograms): your extra stored nutrients
  • 4 pounds (1.8 kilograms): your extra body fluids
Pregnant Woman
Pregnant Woman With Fetus
© Nucleus Medical Media, Inc.

Keep in mind that pregnancy weight gain may vary.

  • If you are underweight, you should gain 28-40 pounds (12.7-18.14 kilograms).
  • If you are overweight, you should gain 15-25 pounds (6.8-11.33 kilograms).
  • If you are obese, you should gain 11-20 pounds (4.9-9.07 kilograms).
  • If you are having multiples (twins, triplets), you will gain more weight, so talk to your doctor about the amount of weight gain that will be best for you.

If you gain too much weight during pregnancy, you will be at increased risk of complications, including diabetes, high blood pressure, constipation, and back pain. In addition, your labor and delivery may be longer and more difficult. You may also be at increased risk of needing a cesarean section.

If you gain too much weight during pregnancy, your baby may also be at risk for being stillborn or having birth defects. Babies born to obese mothers are also at risk for obesity and heart disease later in life.

If you don’t gain enough weight, your baby will not get the nutrients needed to grow and develop properly.

Revision Information

  • Office on Women's Health

    https://www.womenshealth.gov

  • The American Congress of Obstetricians and Gynecologists

    http://www.acog.org

  • The Society of Obstetricians and Gynaecologists of Canada

    https://sogc.org

  • Women's Health Matters

    http://www.womenshealthmatters.ca

  • Eating during pregnancy. Kids Health—Nemours Foundation website. Available at: http://kidshealth.org/en/parents/eating-pregnancy.html. Updated May 2013. Accessed January 30, 2017.

  • Health tips for pregnant women. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/health-topics/weight-control/tips-for-two-pregnancy/Pages/fit-for-two.aspx. Updated June 2013. Accessed January 30, 2017.

  • Leddy M, Power M, Schulkin J. The impact of maternal obesity on maternal and fetal health. Rev Obstet Gynecol. 2008;1(4):170-178.

  • Weight gain in pregnancy. EBSCO DynaMed website. Available at: http://www.dynamed.com/topics/dmp~AN~T115362/Weight-gain-in-pregnancy. Updated July 8, 2016. Accessed January 30, 2017.

  • 6/24/2011 DynaMed's Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T909503/Pregnancy-in-obese-women: Fyfe EM, Anderson NH, North RA, et al. Risk of first-stage and second-stage cesarean delivery by maternal body mass index among nulliparous women in labor at term. Obstet Gynecol. 2011;117(6):1315-1322.

The health information in this Health Library is provided by a third party. Redmond Regional Medical Center does not in any way create the content of this information. It is provided solely for informational purposes. It does not constitute medical advice and is not intended to be a substitute for proper medical care provided by a physician. Always consult with your doctor for appropriate examinations, treatment, testing, and care recommendations. Do not rely on information on this site as a tool for self-diagnosis. If you have a medical emergency, call 911.