Updated

A new study has linked coffee consumption in early pregnancy to a slightly increased risk of having a baby with cleft lip — but the findings shouldn't be cause for alarm, according to one of the scientists who did the research.

"Clefts are a very rare outcome," Dr. Allen J. Wilcox told Reuters Health. "Even if it were true, it would contribute a very small risk to an individual woman. But in fact we don't really know that it's true."

Wilcox, at the National Institute of Environmental Health Sciences/National Institutes of Health in Durham, North Carolina, and colleagues in Norway note in the American Journal of Epidemiology that Norway has a relatively high incidence of cleft lip and cleft palate, at 2.2 children born with the defect for every 1,000 live births. The researchers decided to look at the relationship between consumption of coffee and other caffeinated beverages and orofacial clefts among Norwegians, in part because Norwegians tend to drink a lot of coffee.

The study compared 573 women who had babies with cleft lip with or without cleft palate or cleft palate alone to 763 women whose children weren't born with orofacial clefts.

Compared to non-coffee drinkers, women who drank up to three cups of coffee daily during the first three months of pregnancy were 1.39 times more likely to have a baby with cleft lip with or without cleft palate, while the risk was increased 1.59-fold for women who drank three or more cups of coffee a day.

By comparison, Wilcox noted, having a first-degree relative born with an orofacial cleft increases a person's own risk of the birth defect about 50-fold.

There was no link between coffee consumption and cleft palate only, while women who drank tea actually had a reduced risk of having a child with an orofacial cleft. "If there's something in coffee that is the culprit, it doesn't seem to be caffeine," the researcher said.

Studying the effects of coffee drinking is difficult, he noted, because coffee consumption is related to many other factors; for example, women who drink coffee are more likely to smoke, and their diet is different than that of non-coffee drinkers.

For now, Wilcox added, women who are planning to become pregnant or are pregnant should focus on lifestyle changes that are of proven benefit to babies such as taking folic acid and, if they smoke, quitting.