Effect of Obesity on Pregnancy

Weight is a sensitive topic no matter what size you are. Society sends women messages about how they should look. But if you’re pregnant and clinically overweight or obese—meaning you have a body mass index (BMI) of 25 kg/m2 or greater—and your doctor brings up the topic of weight, they’re interested in the medical implications of obesity on mom and baby. They aren’t judging your appearance. If they do, you might want to find a different doctor.

Most women acknowledge that being overweight comes with health risks. Most can tell you they know that it’s associated with high blood pressure and diabetes. But not everyone knows that being overweight and pregnant (or obese and pregnant) can lead to numerous health issues and complications. Effects of obesity on pregnancy include: 

If you’re overweight or obese, doctors say it’s best to lose weight before you conceive, as being obese can lower your chances of getting pregnant. (Women can often stop ovulating when they’re obese.) If you’re 100-plus pounds overweight you might even consider bariatric surgery, which reduces your appetite by making your stomach smaller.

If you’re already pregnant and obese, you can still enjoy a healthy pregnancy and have a healthy baby. Just work closely with your OB/GYN or midwife to establish the right diet and exercise plan to avoid complications.

How Much Weight Should I Gain?

The American College of Obstetrics and Gynecologists breaks down suggested weight gain by where women fall on the BMI:

  • Obese: 11–20 lbs
  • Overweight: 15–25 lbs
  • Normal weight: 25–35 lbs
  • Underweight: 28–40 lbs

In other words, if you’re overweight and pregnant or obese and pregnant, here is a good rule of thumb.

The number of calories you need to hit those numbers depends on your height, your body mass index (BMI), your activity level, and your metabolism. In general, you don’t need extra calories during the first trimester. Once you reach the second and third trimesters, you’ll need 200-400 additional calories each day.

Try not to get too hung up on the numbers, though. Recommend guidelines act as a reference point for you and your doctor, who cares about your physical and mental health. A significant amount or not enough weight gain can be signs of depression or anxiety. These also have important impacts on your health and the health of your baby.

Being pregnant can be overwhelming. Eat this; not that. Do this; not that. Just remember you’re unique and everyone has a different approach to getting healthy. Find things that are workable and pleasant and not overwhelming.

If you don’t exercise currently, suddenly going to the gym seven days a week can be a recipe for failure. Likewise, you don’t necessarily need to cut out all processed foods and make every meal by scratch using only organic foods. Be thoughtful and consistent—dramatic changes are fine if they are for the better but small changes add up over time to big changes.

Starting Pregnancy Overweight or Obese

Technically, being obese and pregnant classifies your pregnancy as higher risk but that doesn’t mean you’ll definitely have complications.

Finding the right provider to guide you through the journey is incredibly important. At your first appointment, talk to your doctor about your concerns.

He or she might recommend the following:

  • Early testing for gestational diabetes
  • A more detailed fetal ultrasound
  • Screening for obstructive sleep apnea

She or he can also help you set a reasonable exercise plan to keep you on track. Simply walking for 20–30 minutes a day can help reduce the risk of excessive weight gain, gestational diabetes, preeclampsia, postpartum depression symptoms, and lengthy labor. If you snore at night, this may be a sign of sleep apnea and a sleep study can be very helpful in determining if you qualify for treatment.

There is no one-size-fits-all plan to having a baby—your pregnancy is unique and special. Find the right OB/GYN or midwife and they’ll help you achieve your goals.

Next Steps

Concerned about how your weight might be affecting your pregnancy or ability to conceive? Talk to one of our specialists today to learn more about your options. Call 801-581-8425 to schedule an appointment with one of our specialists.

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