Bulimia like Kathy's can ravage the body, causing anemia, dehydration and weakened heart muscles, so women with a recent history of the disorder start pregnancy with more stress on their body than other women do. Women with eating disorders may weigh more than is healthy, too. That's because—contrary to the stereotype of stick-thin disordered eaters—women with bulimia and eating disorders not-otherwise specified (EDNOS) tend to fall on the higher end of the normal-weight spectrum, Bulik says, and binge eaters are often overweight or obese. However often a woman purges, throwing up can never rid the body of all the calories eaten during a binge, she explains.
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It makes sense that if a woman goes into pregnancy overweight, she'll find it much harder to reach a healthy weight afterward, further raising her risk for obesity-related diseases. Her pre-pregnancy weight may also impact the baby. "A women's nutritional status before pregnancy sets the stage for growth of the placenta and how pregnancy progresses, which can have long-term impact on the health of the child," Siega-Riz says.
If Kathy gives in to her eating disorder, she'll raise her risk for gestational diabetes, heart problems, a cesarean section and postpartum depression. For the baby, potential complications of eating disorders include miscarriage, stillbirth, prematurity, low birth weight and breech delivery. The cause of problems in anorexics is pretty clear: inadequate nourishment.
But why would babies of bulimics and binge eaters suffer, too? Scientists aren't sure yet, although they presume it's tied to what they call nutritional dysregulation. "In binge eaters, the baby is exposed to variable energy—bouts of high calories alternating with fasting," Bulik explains. "We're following these kids now to see what the influence of maternal diet is on their weight and growth trajectories."
Women with eating disorders often experience clinical depression, which, if left untreated, can raise the risk for miscarriage, premature birth and low birth weight. Many disordered eaters also take up smoking to try to keep their weight down—some even after they become pregnant.
The encouraging news is that if Kathy does manage to keep on track, she can protect her baby. Women with the healthiest diets before and during pregnancy are 51 percent less likely to have an infant with anencephaly—when the baby is born without part of her brain or skull—and 34 percent less likely to bear a child with a cleft lip, finds a 2011 study of 10,000 women by Stanford University.
Researchers have long believed folic acid is a magic bullet that protected against some of these conditions. But the Stanford findings suggest it's only part of the picture. "Our study showed for the first time that the overall quality of the diet, and not just a single nutrient, matters in terms of reducing the risk for birth defects," says lead author Suzan Carmichael, Ph.D., professor of pediatrics at Stanford. "In our bodies, nutrients don't just act in isolation. They depend on each other."
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Few people knew how poorly Hillary Coggins was eating. Coggins, a 31-year-old graduate student in Bel Air, Maryland, was anorexic as a teenager and has struggled with bulimia for much of her adult life. When she learned she was pregnant nearly three years ago, she hoped the baby would be a catalyst to clean up her diet. Instead, she says, pregnancy brought on still another disorder—binge eating.
"I took the 'eating for two' thing a little too seriously," she says. "I'd bake an entire pan of brownies and eat them all right after they came out of the oven. It was the first time in my life I ate whatever I wanted and didn't worry about it."
Even among non-disordered eaters, this attitude is pervasive and problematic, Siega-Riz notes. "The 'eating for two' myth is the reason for a tremendous increase in gestational weight gain," she says. Most women need only an extra 300 calories a day.
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A petite 5 feet 3 inches, Coggins weighed 139 pounds at her first prenatal visit. By the time she delivered her son, she says she topped 200 pounds. Coggins says she ate "five or six times what someone should," making midnight runs to McDonald's, where she would buy several value meals at a time, or eating six Snickers bars a night for an entire week. She resisted her strong desire to purge, although a few times she vomited simply because she'd overeaten. "I'd eat a carton of ice cream, and then I'd throw up. The irony is that I kept telling myself how unhealthy it was to purge, and yet here I was eating piles of cheeseburgers."
The weight piled on. Between weeks 25 and 36 alone, Coggins packed on 30 pounds. By 37 weeks, she had gained 57 pounds and says she was borderline hypertensive. But despite the signs of overeating, Coggins says, she received only casual lectures on healthy eating. "I vaguely remember my doctor telling me to gain no more than 30 pounds, but by that point, I had already gained that much or more," Coggins says. "Eventually, he commented that eating for two was an expression not to be taken literally, but he never mentioned the health of the baby, only that it would be hard to take off the weight. The message was: You know what to do."
Coggins blames herself for her disordered eating. But, she adds, "if my doctor had said that my weight was endangering me or the baby, I would have tried to curb my habits."
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