Study finds siblings may play key role in women's gestational diabetes risk

NEW YORK A family history of diabetes may increase a woman's risk of developing gestational diabetes, a new study concluded.

Catherine Kim of the University of Michigan Medical School in Ann Arbor and her colleagues examined 4,566 women participating in the "National Health and Nutrition Examination Survey," all of whom had at least one child. Ninety-seven percent had never been diagnosed with diabetes, about 1% had gestational diabetes only, and 2% had Type 2 diabetes. The researchers found a parent with diabetes increased the likelihood of having diabetes or gestational diabetes to a similar degree. But while having two diabetic parents boosted the likelihood of having diabetes eight-fold, it only doubled the likelihood of gestational diabetes.

The risks associated with having a sibling who is diabetic, however, were much higher than having one or even two parents with the disease. Kim and colleagues said this increased gestational diabetes risk more than seven-fold, but only slightly upped the risk of Type 2 diabetes.

"Sibling-only history may be a greater risk factor than previously documented," the authors said.

The findings were published in the December issue of the American Journal of Obstetrics and Gynecology.