Weight gain during pregnancy helps your baby grow. Gaining weight at a steady rate within recommended boundaries can also lower your chances of having hemorrhoids, varicose veins, stretch marks, backache, fatigue, indigestion, and shortness of breath during pregnancy.
Why is weight gain important during pregnancy?
Eating for two is important. The extra weight you gain during pregnancy provides nourishment to your developing baby and is also stored for breastfeeding your baby after delivery.
Eating for Two: Where does all the extra weight go?
Here is an approximate breakdown of your weight gain:
- Baby: 7-8 pounds
- Placenta: 1-2 pounds
- Amniotic fluid: 2 pounds
- Uterus: 2 pounds
- Maternal breast tissue: 2 pounds
- Maternal blood : 4 pounds
- Fluids in maternal tissue: 4 pounds
- Maternal fat and nutrient stores: 7 pounds
How much total weight should I gain?
The amount of weight you should gain depends on your weight and BMI (body mass index) before pregnancy.
You should gain:
- 25-35 pounds if you were a healthy weight before pregnancy, with a BMI of 18.5-24.9.
- 28-40 pounds if you were underweight before pregnancy with a BMI of less than 18.5.
- 15-25 pounds if you were overweight before pregnancy with a BMI of 25-29.9.
- 11-20 pounds if you were obese before pregnancy with a BMI of over 30.
At what rate should I gain weight during my pregnancy?
How much you should gain depends on your weight before you were pregnant and how far along you are in your pregnancy. For the average woman who starts her pregnancy out at a normal weight, your weight gain will look something like this.
If you start out your pregnancy over or under-weight, you will want to talk with your health care provider about what your weight gain rate should look like.
- 1-4.5 pounds during the first trimester
- Approximately 1-2 pounds per week in the second trimester
- Approximately 1-2 pounds per week in the third trimester
Healthy weight before pregnancy:
Throughout your pregnancy the goal is to keep weight gain as steady as possible because your baby requires a daily supply of nutrients that comes from what you eat.
It is normal for your weight gain to fluctuate a little from week to week. However, you should contact your health care provider if you suddenly gain or lose weight, especially in your third trimester. This could be a sign of certain complications.
What if I am carrying twins?
If you are pregnant with twins, your weight gain should be monitored by your health care provider. Weight gain should increase significantly, but will not double. If you are in the normal weight and BMI category before pregnancy, your weight gain should be about 37-54 pounds. Overweight women will aim for a weight gain of 31-50 pounds.
Women who begin pregnancy at an obese weight should strive for a 25-42 pound gain. Of course, these may all be altered by your health care provider’s recommendation and your specific situation.
Does being underweight pose any risks to me or my baby?
Due to morning sickness, many women have trouble gaining weight in the first trimester, and worry about what effects this has on their baby’s development. Some women lose a little weight in the beginning of their pregnancies. Fortunately, at this time, the baby does not need as many calories and nutrients as later in pregnancy.
It is important to gain weight at a steady pace throughout pregnancy. If a woman does not gain weight throughout pregnancy, complications such as a low birth weight or premature delivery could occur. Babies who are born to mothers who do not gain more than 20 pounds are often considered small for gestational age (SGA), meaning they may have been malnourished during pregnancy.
Healthy Eating During Pregnancy:
A sensible meal plan that is rich in vitamins and minerals is essential for a developing baby. You may want to ask your health care provider for food recommendations, or seek the help of a nutritionist in your area. Women who are underweight during pregnancy tend to eat low calorie foods and not enough protein.
The following are ways to get more calories:
- Eat breakfast every day. Peanut butter or a slice of cheese on toast can give you an extra protein boost.
- Snack between meals; yogurt and dried fruits can provide protein, calcium, and minerals.
- Try to eat more foods that are high in good fats such as nuts, fatty fish, avocados, and olive oil.
- Drink juices made from real fruit that are high in vitamin C or beta carotene, such as grapefruit juice, orange juice, papaya nectar, apricot nectar, and carrot juice.
- Avoid junk food. (learn more about foods you should avoid)
- Consult your health care provider about taking prenatal vitamins and any additional supplements.
Can gaining too much weight be harmful?
The following are potential problems with gaining too much weight:
- Gestational diabetes
- Leg pain
- Increased fatigue
- Varicose veins
- Increased risk of cesarean delivery
- High blood pressure
How does being obese affect my pregnancy?
Many overweight women have healthy pregnancies and deliver without complications. However, it is important to be aware of the potential risks that extra weight can have.
Pregnant women who are struggling with obesity may have:
- An increased risk for gestational diabetes and high blood pressure
- Difficulty with hearing the heartbeat and measuring the size of the uterus
- Difficulty with vaginal delivery if the fetus is much larger than average
Fortunately, appropriate medical and self care can lower the risks of these complications. Your health care provider may suggest that more tests be done during pregnancy. These might include ultrasounds to measure your baby’s size, a glucose tolerance test to screen for gestational diabetes, and other diagnostic tests later in pregnancy to monitor your baby’s development.
The following self care tips can help you make your pregnancy a healthy one for you and your baby:
- Avoid pregnancy risks such as alcohol and smoking.
- Try not to gain too much weight; your health care provider will provide recommended weight gain.
- Be selective about your food choices; choose food sources that contain vitamins, minerals, and protein.
Last Updated: 07/2015
Compiled using information from the following source:
American Congress of Obstetricians and Gynecologists, https://www.acog.com
Institute Of Medicine, Report Brief May 2009, Weight Gain during Pregnancy: Reexamining the Guideline, https://www.iom.edu