Thomseth V, et al. - Whether an increased risk of malformations is seen, in humans, in relation to exposure to antazoline-naphazoline eye drops in the first trimester of pregnancy, was determined in this nationwide cohort study including all women giving live birth between 1997 and 2011 in Denmark. In the first trimester of pregnancy, exposure to antazoline-naphazoline eye drops was reported in overall 3061 women (0.32%). Between 1997 and 2011, a total of 977,706 births were identified. According to the findings, there appeared no link between exposure to antazoline-naphazoline eye drops in the first trimester of pregnancy and an increased teratogenic risk.