Rethinking How Much Weight to Gain During PregnancySep 4, 2014
When you get pregnant, you need to eat for two, right? Dr. Kirtly Jones says otherwise. She reveals the most recent findings and explains the guidelines for pregnant moms of all shape and sizes. Find out where (on the scale) you belong.
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Interviewer: Dr. Jones, I'd like to you talk a little bit about women who are overweight, eating, and pregnancy. Now you've often said that you don't have to take that many extra calories in, but how about for an overweight woman? Additional calories at all or can the fat provide the energy?
Dr. Jones: It turns out that the fetus is an excellent parasite. It gets what it needs. Although we've always associated weight gain with healthy outcomes and the absence of weight gain with not such great outcomes. For women who are overweight already, who might be carrying an extra 30 or 40 pounds, the national consensus now is they should probably not necessarily lose, but not gain any weight at all. So if you're 30 pounds overweight, maybe 10 pounds is the total weight gain. If you're 60 pounds overweight, maybe nothing.
Now that doesn't mean you starve. It means that you need to be careful to look at your nutrient content. So you want to take your prenatal vitamins, hopefully this is a planned pregnancy and you started your vitamins before you got pregnant, because women who are obese have a higher rate of neural tube defects. Those include spina bifida, meningomyelocele, and some very significant problems for babies. Obese women should be taking prenatal vitamins even before they get pregnant.
So maybe 10 pounds if you're 10 to 30 pounds overweight. But if you're more like 60 pounds overweight, no weight gain is actually good as long as women are eating an appropriate caloric diet. You've all seen pictures of refugee camps where women who look like they're skin and bones are nursing a skin and bone baby. How did they get pregnant and grow that baby in the first place? That's where the baby and the placenta pumps calories from your body into the baby. Nutrients, that means vitamins and minerals and protein and calcium, these are important but the extra calories are not.
Interviewer: Is it okay for somebody that's 30-40 pounds overweight that's carrying a child to be on a diet?
Dr. Jones: Our goal is not to have a calorie deficient diet. We normally don't encourage women who are 40 pounds overweight try to lose weight during pregnancy. If they don't gain very much, if they only gain 10 pounds, then that means that they're being pretty careful about what they're eating and if they start moving, they functionally will have lost 20 pounds after the baby is born and they deliver the baby, they deliver the placenta, they deliver the amniotic fluid, they get rid of all that water weight. Then they will have lost about 10 pounds. So we don't encourage women to actually lose weight during pregnancy, but we don't encourage them to gain very much either.
There are women who develop a pretty significant problem during pregnancy of nausea and vomiting. These women may actually lose weight in the first trimester because they are so nauseated and they throw up all the time. It turns out that having pretty significant nausea and vomiting in the first trimester is associated with a really good pregnancy outcome. Go figure. So women may actually lose five or more pounds in the first trimester because they're nauseated and they don't feel like eating very much. Now if you take that nausea and you feed it crackers all the time, of course you're going to gain a little bit. But having a whole lot of nausea and vomiting such that you lose weight in the first trimester, that isn't associated with a bad outcome. We do encourage women to not get dehydrated because that can be a bad thing.
In sum, the baby will pump the calories it needs most of the time. Losing weight in the first trimester is not a good thing if it's done deliberately, but we have examples of women who have pretty bad hyperemesis we call it, pregnancy, and they're babies turn out okay as long as they can nurse themselves adequately with protein, particularly in the second trimester. If you're starting off your pregnancy, and hopefully it's a planned one and you took your vitamins before you got pregnant, and you're 60 pounds overweight, then no weight gain would be probably very appropriate. It's hard to do because often you're hungry, but this is a time to start moving because you definitely want to get moving to push that baby out, get fresh air after the baby is born.
Interviewer: So for somebody that's 30-40 pounds overweight, should they eat additional calories in the second and third trimester?
Dr. Jones: Well that's going to be one that you want to discuss with your midwife or your OB. Your midwife or OB should be aware of the stratified weight gain recommendations, meaning women are recommended to gain 20 to 25 pounds if they're normal weight and maybe only 10 to 15 pounds if they're overweight to obese. If they're very obese, maybe no weight. Your midwife or OB should know that we have new recommendations. Losing weight is not necessarily a good idea because if you don't gain any, you'll lose 30 pounds at delivery. So by not gaining any weight, you will be functionally losing fat, hopefully not muscle because you'll be moving. Overweight is a BMI between 26 and 30, so that's not very overweight.
Interviewer: In some instances, they might not need any more calories than what they normally eat.
Dr. Jones: Obese women do not need more calories than what they're already eating unless they started off starving themselves when they got pregnant. Obese women don't need any extra calories. That 300 extra calories, those 3 glasses of 2% milk, they don't even need that because they'll probably be able to shift some calories in their own storage. But they should eat nutritionally balanced diets.
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