PREGNANCY WEIGHT AND OBESITY

Gaining too much weight — or too little — during pregnancy is associated with an increased risk that your child will be obese as a preschooler, new evidence shows.

Institute of Medicine guidelines for pregnancy weight gain range from 28 to 40 pounds for underweight women, 25 to 35 pounds for normal weight women, 15 to 25 pounds for overweight women and 11 to 20 pounds for obese women.

Researchers followed 4,145 women from before they became pregnant until their children were 2 to 5 years old.

The study appears in The American Journal of Obstetrics & Gynecology.

Compared with children of mothers who met the guidelines, children of mothers who gained more had a 46 per cent increased risk of being overweight or obese.

The researchers adjusted for mothers’ age, race, diet, education, BMI before becoming pregnant and other characteristics.

The effect was even more marked for women who were not overweight: in that group, gaining more increased the risk of having an obese child by 79 per cent, and gaining less increased it by 63 per cent.

“More than half of women gain too much during pregnancy,” noted the senior author, Monique M. Hedderson, a research scientist at Kaiser Permanente Northern California.

“Only 10 per cent of women are gaining too little.”

Less vitamin D, more cavities

Low levels of vitamin D in pregnancy are associated with the development of cavities in babies, researchers report.

The scientists studied 134 expectant mothers, average age 19.

Each provided information on health behavior and socioeconomic status and gave blood samples to measure vitamin D levels.

Their children had dental examinations when they were an average of one year old, and their mothers completed another questionnaire on health and behavioral factors. About a third of the women were deficient in vitamin D, 22 per cent of the infants had deficient or thinning enamel and 23 per cent had cavities.

After controlling for other factors, they found that the lower the prenatal vitamin D level in the mother, the higher the number of cavities in the child.

Defective enamel and prenatal vitamin D levels were both independent predictors of cavities.

The authors acknowledge that the study, published in Paediatrics, has shortcomings. It was not a randomized trial, the population was economically disadvantaged, and they could not control for all factors potentially associated with tooth decay.

But, said the senior author, Robert J. Schroth, an associate professor at the University of Manitoba, “this may be the first step in prevention — making sure that prenatal nutrition and vitamin D levels are right.”

New York Times Service