Women who regularly consume soft drinks may be reducing their chances of getting pregnant, according to new research.
A study of 524 patients found a link between artificial sweeteners, such as those used in “diet” sodas, and lower fertility rates, while use of sugar in soft drinks and added to coffee was associated with poorer quality of eggs and embryos.
One of Britain’s leading fertility experts last night described the findings as “highly significant”, and warned women not to underestimate the effects of food additives on their likelihood of conception.
Other scientists, however, have said the lower pregnancy rates may have been driven by obesity, which is already a known negative factor, rather than the sugar or its synthetic equivalent per se.
Artificial sweeteners, such as saccharin and sucralose, are chemical substances that many people choose over sugar because they are low-calorie or calorie-free.
In the study, which will be presented today at the American Society for Reproductive Medicine congress in Salt Lake City, a batch of women who were undergoing IVF treatment were interviewed by nutritionists about the foods they consumed, as well soft and hot drinks.
The finding, showed that reduced rates of pregnancy was most closely associated with consumption of soft drinks made with artificial sweeteners, as well as coffee with added artificial sweeteners.
Meanwhile the use of sugar in soft drinks and coffee was associated with a poorer quality of egg, which can be a factor in likelihood of getting pregnant.
Unsweetened coffee, however, had no effect on egg quality or pregnancy chances, said the researchers from the Federal University of Sao Paulo.
Professor Adam Balen, Chairman of the British Fertility Society, said: “This is a very interesting study that suggests the false promise of artificial sweeteners that are found in soft drinks and added to drinks, such as coffee, may have a significant effect on the quality and fertility of woman’s eggs and this may further impact on the chances of conception.
“These findings are highly significant to our population.
“There should be more scrutiny of food additives and better information available to the public and, in particular, those wishing to conceive.”
However, a spokesman for the British Dietetic Association said the study made no effort to distinguish the effect on fertility outcomes of the bodyweight of the women in the trail from the impact of artificial sweeteners and sugar in their diets.
Professor Sir Colin Berry, Emeritus Professor of Pathology at Queen Mary University London, also cautioned about drawing inferences on wider reproductive outcomes from the experience of IVF patients.