Aspartame Causes Premature Births

Researchers interviewed almost 60,000 pregnant Danish women about their soft-drink consumption, then compared these data with the results of the women's births. They found that drinking one can of diet soda per day increased her risk of giving birth prematurely by 38 percent compared with women who never drank diet soda. Drinking four or more of the beverages per day increased the risk of preterm birth by 78 percent.

A preterm birth is defined as taking place before the 38th week of pregnancy.

No connection was found between sugared soda consumption and premature birth, suggesting that artificial sweeteners may be playing a role in the effect. The researchers suggested that premature births may be triggered in part by the neurotoxin methanol, which is generated by some artificial sweeteners. Sweeteners may also generate formaldehyde, another known toxin.

Prior studies have also shown that the artificial sweetener saccharin builds up in the placenta.

"I would think it is prudent for pregnant women to diminish consumption of these drinks and possibly those foods containing artificial sweeteners," said Erik Millstone of the University of Sussex.

Mary Ellen Sherry of the University of Tennessee Medical Center was cautious about the results, noting, "There are a lot of risk factors for prematurity. Poor nutritional health is one. Underweight is one."

She urged women to start taking care of their bodies and eating a balanced diet even before becoming pregnant, if possible, making sure to get plenty of protein, calcium and folic acid.

As for diet soft drinks, she pointed out that they provide no nutritional benefit to your diet, so you lose nothing by giving them up.

"If you are afraid of it, don't do it," she said. "That's one thing that's easy to give up, diet drinks."