A recent study has purportedly linked consumption of carbonated diet sodas with an increased risk of premature birth. Thorhallur Halldorsson, et al., “Intake of artificially sweetened soft drinks and risk of preterm delivery: a prospective cohort study of 59,334 Danish pregnant women,” American Journal of Clinical Nutrition, June 30, 2010. Researchers evaluated data from approximately 60,000 pregnancies tracked in Denmark between 1996 and 2002. According to the study, women in the middle of their pregnancies who drank at least one diet soft drink daily were 38 percent more likely to have a premature baby before 37 weeks of pregnancy than those who abstained. In addition, women who drank at least four such products per day were at a 78 percent risk of early delivery.  

The researchers claimed that “no association was observed for sugarsweetened carbonated soft drinks or for sugar-sweetened noncarbonated soft drinks” and suggested that more studies are needed to reject or confirm their findings. Halldorsson told a news source that “it may be non-optimal” for pregnant women to drink artificially sweetened beverages in high amounts. Although the study did not evaluate specific artificial sweeteners, Halldorsson cited indirect evidence linking aspartame to premature births in animals. See Reuters, July 26, 2010.