New York ? Treating even mild diabetes that develops during pregnancy helps keep moms and babies from gaining too much weight and makes for easier deliveries, new research shows.

Pregnant women in the U.S. are routinely tested and treated for high blood sugar levels, although it hasn’t been clear whether treating the mildest cases really benefited them and their infants.

In a study of 950 women, those with mild gestational diabetes who were treated had fewer overly large babies, cesarean sections and pregnancy complications compared with women who didn’t have their diabetes treated.

“There is every reason to fully treat women with even the mildest (gestational diabetes) based on our results,” said study leader Dr. Mark Landon of Ohio State University Medical Center in Columbus.

Gestational diabetes begins during pregnancy and usually goes away after childbirth. It affects as many as one in seven pregnant women, depending on the population. The mother’s elevated blood sugar can cause the fetus to grow too large, sometimes requiring a C-section and can bring on other health problems for the mother and baby.

Risk factors include being over 25, being obese and a family history of diabetes.