Your weight gain, how much and the way you gain, is a good way to tell if your pregnancy is going well. By tracking your weight gain, health professionals know how well your pregnancy is progressing and how your baby is growing too.

So How Much Weight Should You Gain for a Healthy Pregnancy?

The weight gain that is right for you depends on what you weighed before pregnancy. You should aim to gain:

  • 25 to 35 pounds if you were within a Healthy Weight range before pregnancy.
  • 28 to 40 pounds if you were Underweight before pregnancy. Both you and your baby will benefit if you gain a little extra.
  • 15 to 25 pounds if you were Overweight before pregnancy. A smaller weight gain will provide for your baby without putting extra weight on you.
  • 11 to 20 pounds if you were Obese before pregnancy. A smaller weight gain will provide for your baby without putting extra weight on you.

The weight you gain is made up of:

  • ž the baby’s weight – ideally 6 to 8 pounds (2500 to 3500 grams) at birth
  • ž the weight of the placenta and amniotic fluids – 4 to 6 pounds
  • ž the weight of a larger uterus – 2 to 3 pounds
  • ž the weight of extra blood – 4 pounds
  • ž the weight of larger breasts – 2 to 3 pounds
  • ž the weight of extra fluids – 2 to 3 pounds
  • ž the weight of some extra body fat on you – 5 to 8 pounds (mother nature’s way of making sure you will have sufficient energy to produce breast milk).

Use the Body Mass Index chart below to find out whether you were within a healthy weight range, underweight, overweight, or obese before pregnancy.

Instructions: Find your height in the bolded numbers column on the left. Move across the table until you find your pre-pregnancy weight in pounds. The number at the bottom of this column is your pre-pregnancy Body Mass Index.
 Weight in Pounds
Height in Inches58889196100105110115119124129134138143148153158162167172177
59919499104109114119124128133138143148153158163168173178183
609597102107112118123128133138143148153158163168174179184189
6198100106111116122127132137143148153158164169174180185190195
62101104109115120126131136142147153158164169175180186191196202
63104107113118124130135141146152158163169175180186191197203208
64108110116122128134140145151157163169174180186192197204209215
65111114120126132138144150156162168174180186192198204210216222
66114118124130136142148155161167173179186192198204210216223229
67118121127134140146153159166172178185191198204211217223230236
68121125131138144151158164171177184190197203210216223230236243
69125128135142149155162169176182189196203209216223230236243250
70129132139146153160167174181188195202209216222229236243250257
71132136143150157165172179186193200208215222229236243250257265
72136140147154162169177184191199206213221228235242250258265272
Body Mass Index18.519202122232425262728293031323334353637

What does your pre-pregnancy Body Mass Index mean?

If your Body Mass Index was:

  • Below 18.5 – you were likely Underweight
  • 18.5 to 24.9 – you were within a Healthy Weight range
  • 25.0 to  29.9 – you were likely Overweight
  • 30.0 or higher – you were Obese

Guide for Gaining Weight

The way you gain weight is just as important as the total weight gained. In the first 12 weeks (first trimester) weight gain should be minimal, about one to four pounds. Every week thereafter, there should be a small and steady gain of half pound to one pound depending on your pre-pregnancy weight. Large ups and downs in weight are cause for concern and should be discussed with your health care professional.

The table below will guide your pregnancy with a healthy weight.
Weight Before Pregnancy - Body Mass IndexTotal Gain in poundsFirst Trimester Gain - one to three months
Weekly Gain Thereafter
Underweight - below 18.528 to 401 to 4 pounds1.0 pound
Healthy Weight - 18.5 to 24.925 to 351 to 4 pounds1.0 pound
Overweight - 25.0 to 29.915 to 251 to 4 pounds0.6 pound
Obese - above 30.011 to 20 1 to 4 pounds0.5 pound

What About Twins?

If you are having more than one baby you need to gain even more weight. Women within a healthy weight range should gain a total of 37 to 54 pounds, overweight women 31 to 50 pounds and obese women 25 to 42 pounds. At this time there is not enough information to develop guidelines for underweight women carrying twins and for women carrying more than two babies.

Healthy Eating for a Healthy Baby and Healthy Weight Gain

If your eating habits are not the best, this is the time to make healthy eating a priority. You need some extra food during pregnancy but not a lot. During your first trimester no extra calories are needed. In the second and third trimester you need a small amount of extra food each day. Try to:

  • Eat healthy foods – vegetables and fruit, whole grain products, and protein food including lean meat, low-fat dairy, fish, beans, lentils, tofu, nuts and seeds.
  • Limit foods that are non-nutritious such as sweets, salty snack foods, pop and pastries.
  • Eat when you are hungry and stop when you are satisfied.
  • Remain active. Try walking during pregnancy. You will feel better for it.