This sheet is about obesity in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is obesity?
Obesity is a condition that is associated with too much body fat. One measure of obesity is body-mass index (BMI) which is an estimate of body fat based on height and weight. A person is said to be obese when their BMI is 30 or higher and overweight when their BMI is between 25 and 29.9. To learn what your healthy weight range is, visit the The Centers for Disease Control and Prevention website: https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/english_bmi_calculator/bmi_calculator.html
What about weight gain during pregnancy?
Weight gain during pregnancy is expected. The ideal amount of weight gain during pregnancy will vary with your pre-pregnancy BMI and the number of babies that you are carrying. People who are pregnant and overweight or obese may be encouraged to limit weight gain during pregnancy. In general, a total weight gain of 15–25 pounds for people who are overweight and 11–20 pounds for people who are obese is recommended during pregnancy. It is important to work closely with your healthcare providers to determine how much weight you should gain during pregnancy.
Should I try to lose weight while pregnant?
Weight loss is generally not recommended during pregnancy. Ideally, weight loss should be done before pregnancy. Losing even a small amount of weight can improve your overall health and pave the way for a healthier pregnancy. If you are already pregnant and overweight or obese, limiting your weight gain might be recommended. Talk with your healthcare provider about your recommended weight gain, nutrition, and exercise.
I am obese. Can it make it harder for me to become pregnant?
Studies have shown that it takes longer for people who are obese to get pregnant and that they may have a lower chance of getting pregnant naturally.
Can obesity increase the chance for miscarriage?
Miscarriage can occur in any pregnancy. Obesity has been associated with a slightly higher chance for miscarriage. For example, every pregnancy has approximately 15-20% chance of miscarriage. Obesity may increase that chance to 18-24%.
Can obesity increase the chance of birth defects?
Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Obesity during pregnancy has been associated with a higher chance for certain birth defects, such as problems with the heart and spine. However, the overall increased chance for birth defects is likely to be small. For example, about 1-2 babies of every 1,000 (0.1-0.2%) born will have a neural tube defect, which occurs when the spine or skull does not close properly. Obesity may double that chance, meaning that the actual increased risk is still small at 2-4 babies out of 1,000 (0.2-0.4%) babies born. Ultrasounds (sound wave pictures of the baby) are used to screen a pregnancy for birth defects. However, obesity can make it harder for birth defects to be detected by ultrasound.
Can obesity increase the chance of other pregnancy related problems?
Obesity has been found to increase the chance for gestational diabetes, high blood pressure and other health complications during pregnancy. Obesity might also cause an increased chance of preterm delivery (birth before week 37) and stillbirth. Also, babies of people who are pregnant with obesity are at an increased chance for large body size (macrosomia) which can make delivery more complicated. Obesity has also been associated with a greater chance for a c-section delivery.
Can obesity in pregnancy affect future behavior or learning for the child?
Some studies have suggested a possible association with learning difficulties and attention deficit/hyperactivity disorder in children born to people who are obese. However, this is difficult to study and this association in not clearly proven. Obesity in in pregnancy is also associated with an increased chance of childhood obesity, metabolic problems, and asthma.
Breastfeeding while I am obese:
Obesity is not considered a reason for concern with breastfeeding. Be sure to talk to your healthcare provider about all your breastfeeding questions.
If a male has obesity, can it make it harder to get a partner pregnant or increase the chance of birth defects?
Studies have found that obesity in males can reduce fertility (make it harder for them to get a partner pregnant. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.
Please click here to view references.
OTIS/MotherToBaby encourages inclusive and person-centered language. While our name still contains a reference to mothers, we are updating our resources with more inclusive terms. Use of the term mother or maternal refers to a person who is pregnant. Use of the term father or paternal refers to a person who contributes sperm.
