Women who eat more potatoes before pregnancy may be at a higher risk of gestational diabetes - the form that occurs during pregnancy - compared to women who consume fewer potatoes, a new study says.

The researchers suggested that substituting potatoes with other vegetables, legumes or whole grains may help lower gestational diabetes risk.

Gestational diabetes is a common pregnancy complication that causes high blood sugar levels in the mother and the disorder can lead to future health problems for both mother and child.

The researchers from the US National Institutes of Health (NIH) and Harvard University evaluated more than 15,000 women from 1991 to 2001 who had no history of illness before pregnancy and had no gestational diabetes before.

Every four years, the women filled out a questionnaire on the kinds of foods they had eaten during the previous year. For potatoes, the women were asked if they had consumed baked, boiled, or mashed potatoes, fries or potato chips.

The researchers found that women who ate more potatoes had a higher risk of gestational diabetes.

The findings appeared in The BMJ (formerly the British Medical Journal).