In the study, published in the Archives of Internal Medicine, researchers looked at data on nearly 571,000 births in Denmark from 2000 to 2008, Reuters.com reported.
On the whole, 2 to 3 out of every 100 infants had a birth defect.
However, of the 149 women who used Malarone during the first trimester at some point, roughly one of every 100 had a baby with a birth defect, according to the news agency.
Reuters.com quoted Copenhagen-based Statens Serum Institute lead researcher Bjorn Pasternak as saying that the findings offer some reassurance that the drug is not linked to any large risk of birth defects, but since only a small number of women in the study took Malarone during early pregnancy, the findings cannot rule out the possibility of some risk.
"We believe it is far too soon to declare this drug to be safe for use in pregnancy," Pasterak told Reuters Health in an email.