Not Gaining Weight During Pregnancy? What is normal and what is not

It only makes sense that being pregnant means gaining a few extra pounds – your body literally grows into a different person. For most pregnant women, some weight gain is not only expected, it is encouraged. But for some, the number on the scale isn’t really rising, and they may be wondering if it’s normal not to gain weight during pregnancy, or if there’s something wrong. When you hear some pregnant people talk about gaining 30, 50, or 100 pounds while pregnant but not gaining any weight, it can be unnerving. Before you freak out, take a deep breath and remember that your weight during pregnancy — weight gain or weight loss — doesn’t always mean there’s something wrong with the baby.

Is it normal not to gain weight during pregnancy?

Only about a third (32%) of women gain the recommended amount of weight during pregnancy. According to the Centers of Disease Control and Prevention (CDC), most women (48%) gain more than recommendations, and some women (21%) gain less. The weight gain that your doctor or nurse will usually suggest depends on your body mass index (BMI). This means that recommended average weight gain recommendations will vary from person to person. This makes it difficult to say what is truly “normal” and what is not, explains dr Mary Jacobson, MD, OB-GYN and Senior Medical Advisor for Alpha Medical. The reason obstetricians care about your number on the scale — and may be concerned if you don’t gain weight during pregnancy — is because gaining weight below the recommended amount can be associated with birthing smaller babies, those with one of your own Set of risks can come, such as difficulty breastfeeding and increased risk of disease.

Despite this, it can sometimes be difficult for a pregnant woman to gain weight. Jacobson notes that the following may contribute to little or no weight gain during pregnancy:

  • calorie restriction
  • Hyperemesis gravidarum, a condition that causes severe nausea and vomiting during pregnancy
  • Autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus
  • Cancer

Keep in mind that weight gain doesn’t always happen in the first few weeks of pregnancy, especially if you’re experiencing severe nausea or morning sickness and have trouble keeping food down. If you don’t gain weight in the first trimester of pregnancy, rest assured that you are in good company. For many pregnant women, pregnancy weight gain does not start until the second trimester. In fact, some women with morning sickness actually lose weight in the first trimester, dr Jill Purdie, MD, OB-GYN and medical director at Northside Women’s Specialists in Atlanta, Georgia, tells Romper. The weight often regains when the nausea and vomiting stop. If you’re having trouble maintaining your weight in the first trimester, don’t stress. Just make sure to drink plenty of water, Purdie reminds, because it’s easy to become dehydrated during pregnancy.


How much weight gain during pregnancy is considered normal?

There is no ideal weight you should aim for during pregnancy, as “normal” weight varies from person to person. “How much weight a person should gain during pregnancy depends on their body mass index,” explains Jacobson. “BMI is a measure of body fat based on height and weight. It can be calculated using pounds and inches: BMI = (weight in pounds x 703) / (height in inches x height in inches). It also depends on whether they have a singleton or multiple (more than one fetus in the womb) pregnancy.”

That Institute of Medicine provides a chart of expected weight gain during a singleton or twin pregnancy that Jacobson recommends viewing and following. In the case of a singleton pregnancy:

  • If you had a BMI below 18.5 before pregnancy, you should gain 28-40 pounds.
  • If you had a BMI between 18.5 and 24.9 before pregnancy, you should gain 25-35 pounds.
  • If you had a BMI between 25 and 29.9 before pregnancy, you should gain 15 to 25 pounds.
  • If you had a BMI over 30 before pregnancy, you should gain 11-20 pounds.

Keep in mind that these are general recommendations. If you have not yet gained weight during pregnancy, talk to your doctor. If they’re not worried, then you probably don’t have to be either.

When to worry about your weight during pregnancy

Everyone’s body is different, which means not everyone will gain the recommended amount of weight during pregnancy — and sometimes that’s totally fine. However, sometimes there is a concern about not gaining weight during pregnancy. Your doctor will likely check your weight at each appointment. If they see something that worries them, they will investigate. Or, if you’re concerned, feel empowered to ask them for more information.

“If the size of your uterus, measured as the fundus height from your pubic bone to the top of your uterus, is not gradually increasing after 20 weeks of pregnancy, your obstetrician will recommend a “growth scan,” or abdominal ultrasound, to measure various aspects of the fetus, such as head circumference , abdominal circumference and femur length, and pockets of amniotic fluid around the fetus to create a treatment plan,” says Jacobson.


How to gain weight with severe morning sickness

Again, it’s extremely normal not to gain much weight during the first trimester of pregnancy, and those struggling with morning sickness may even lose weight. However, if you’re concerned, try eating small, frequent meals. The food you eat should be high in carbohydrates and low in fat. If you know certain foods make you feel sick, avoid them at all costs. Eat foods higher in protein and calories, like protein shakes or shakes with supplements, advises Purdie.

Other popular remedies for first trimester nausea include ginger tea, acupressure devices such as Sea-Bands, or a combination of vitamin B6 and Unisom before bed. Make sure you check this — and any new medications — with your OB-GYN before trying them.


dr Mary JacobsonMD, OB-GYN and Chief Medical Advisor for Alpha Medical

dr Jill PurdieMD, OB-GYN and Medical Director at Northside Women’s Specialists

Comments are closed.