Fetal Exposure to Montelukast and Congenital Anomalies: A Population Based Study in Denmark.

Background: The objective was to study pregnancy outcomes between groups of Danish women, with pregnancy ending between 1998 and 2009, according to their exposure to montelukast.

Methods: Cross-sectional observational study in Danish women, selecting live births and stillbirths (Birth Registry) and spontaneous abortions and induced terminations (Patient Registry). Montelukast exposure was obtained from the Prescription Registry (ATC code R03DC03).