By Patricia Reaney
London - Drinking moderate amounts of caffeine during pregnancy does not lead to premature births or underweight babies, Danish scientists have said.
Up to three cups of coffee a day does not seem to have any negative impact on the baby or the pregnancy.
Earlier studies that looked at the impact of moderate caffeine consumption during pregnancy have produced mixed results. Some showed no difference while others suggested too much caffeine could lower average birth weight by 100g to 200g.
"In our study we found no effect from caffeine," said Dr Bodil Hammer Bech, of the Institute of Public Health in Aarhus, Denmark.
Unlike other research projects in which women who had given birth were asked how much coffee they drank while pregnant, the Danish scientists monitored 1 207 pregnant coffee lovers who were randomly selected to drink either a caffeinated or decaffeinated brew during the second half of the pregnancy.
The women did not know which group they were in.
"We had two groups and we actually found no difference between the average birth weight for moderate intake of caffeine - about three cups," said Bech, whose findings are reported online by the British Medical Journal.
"The difference in the weight of the babies between the two groups was 20g and there was no difference in the gestational age," she said.
In the caffeinated group, 4,2 percent of babies were born premature compared to 5,2 percent in women drinking decaffeinated coffee. The number of infants who were small for their gestational age were nearly the same in both groups.
Bech said women who drink a lot of coffee usually smoke and drink more alcohol than other females, which could influence birth weight.
But because the women were randomised in the study, the other factors that may have an effect on the baby and the pregnancy were equal in the two groups.
In an earlier study, Bech and her team showed that excessive coffee consumption, eight cups or more, could increase the risk of stillbirth.
"About three cups of coffee a day is okay but women with a higher intake should be careful," said Bech.