WEDNESDAY, Dec. 10, 2003 (HealthDayNews) -- When it comes to the health of their newborns, women who are conceiving or who are already pregnant should be worried about more than just folic acid.
New research from the latest issue of the American Journal of Epidemiology suggests women who diet or fast early in their pregnancy seem to have a substantially higher risk of having babies with neural tube defects.
Neural tube defects (NTDs) are one of the most common birth defects and refer to incomplete development of the spinal cord or brain, such as spina bifida. According to Duke University, up to 70 percent of neural tube defects can be prevented by having expectant mothers take extra folic acid, a B vitamin.
"Everybody is very sensitive to the B vitamin family for folic acid and NTDs, but now we see it's obviously much more complex than just the decrease or absence of a single nutrient," says Dr. Maureen Malee, director of maternal/fetal medicine and chief of obstetrics at the University of Miami School of Medicine. "You have to look at the whole picture."
For this study, the researchers from the March of Dimes and the California Birth Defects Program interviewed about 500 mothers of children with NTD defects (including anencephaly, spina bifida, craniorachischisis, or iniencephaly) and about another 500 mothers of children without defects. All the women had delivered between 1989 and 1991 in various counties in California.
The mothers were asked whether, during the three months before conception and each trimester of pregnancy, they had been on "a diet to lose weight," "a diet that involved any fasting," or "any other type of special diet"; whether they had "an eating disorder"; and whether they ate "freezer frost, cornstarch, or laundry starch," "plaster, clay, or dirt," or "any other items like these."
Women who answered yes to "other special diets" or "eating disorders" were asked to give additional details. All the women were also asked if they had engaged in specific behaviors such as taking diet pills, diuretics or laxatives, binge eating, induced vomiting or excessive exercising.
Researchers were most interested in eating behaviors during the first trimester, the critical time for neural tube development.
Women who reported being on diets to lose weight or who had eating disorders during the first trimester had about double the risk of giving birth to babies with NTDs. Those who fasted during this time had almost six times the risk.
Women who took diuretics any time during their pregnancy or the three months before conception also seemed to have a higher risk of having babies with one of these disorders.
"Pregnancy isn't a time to be dieting. There's consequences about which we are unaware, and this is a newly found consequence," Malee says. "We do not yet understand the complex interplay of nutrients you have in a well-balanced diet, and that's what you need to be sensitive to. You can't diet and take additional folic acid. That's not going to do the trick. You have to have a well-balanced diet."
More information
For more on neural tube defects, visit Duke University Medical Center or The Arc.
