Why We're Probably Wrong About Pregnancy Weight Gain

Photographed by Megan Madden.
As a society, we're not great at letting pregnant people just, you know, be pregnant — especially when it comes to their weight. Blac Chyna got a fair amount of internet wrath for embracing her weight gain, and even Queen Bey was not immune to weight-based pregnancy speculations. But please, let's try to internalize this truth: Whether or not someone else's pregnancy body is "okay" should be left between that person and that person's doctor.
"There is no black and white," says Diana Ramos, MD, associate clinical professor of obstetrics and gynecology at the Keck University of Southern California School of Medicine. In general, she says doctors consult official guidelines for weight gain week-by-week and throughout the pregnancy overall. But each patient's case is different, and doctors take a bunch of other factors into account when looking at whether or not that patient's weight is healthy.
According to the guidelines from the Institute of Medicine, the amount of weight you should expect to gain during your pregnancy depends on your pre-pregnancy weight. For women who are underweight, they may gain between 28 and 40 lbs throughout their pregnancy, while women who are obese should only expect to gain between 11 and 20 lbs.
That's why Dr. Ramos says "the best time to even think about weight gain is before you become pregnant." That means, if you're thinking about becoming pregnant, check in with your doctor to discuss where you're at now and what you have to look forward to.
There are also weekly weight-gain guidelines, but not everyone gains weight in the same amount of time, Dr. Ramos explains. Some women gain a lot of weight in just a few weeks while others gain it more steadily over time. Many of us looking and judging others for their weight are only seeing them in one particular snapshot of their lives, and we don't know how that weight is going to change in a month or even in a week.
Those guidelines exist because there are risks associated with certain patterns of weight gain during pregnancy. Gaining too much weight increases your risk for gestational diabetes and the need for a C-section (which comes with its own set of risks). Being underweight puts you at a higher risk for preterm delivery and giving birth to a baby at low weight.
But weight (specifically BMI) is far from the only factor in determining the health of a pregnant person. "[Doctors] ideally want to make recommendations to also eat healthier, take prenatal vitamins, and walk as much as possible," Dr. Ramos says. At the same time, however, each patient's history will help guide those recommendations. If someone had gestational diabetes during her previous pregnancy, for instance, keeping an eye on nutrition may be a more central part of her current pregnancy.
But weight — however it appears — is never the full story.

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