Andersson NW, et al. - In this nationwide, registry-based cohort study, researchers intended to determine if there is a connection between oral and topical terbinafine exposure in pregnancy and the risk of major malformations and spontaneous abortion. This investigation was carried out in Denmark from January 1, 1997, to December 31, 2016, in a cohort of 1, 650,649 pregnancies. This analysis involved all pregnancies with use of oral and topical terbinafine in pregnancy during the study period 1997-2016 (n = 4,065) as well as 40,650 unexposed pregnancies. Pregnancies were matched by propensity scores contrasting oral terbinafine exposed vs unexposed (1:10 ratio), topical terbinafine exposed vs unexposed (1:10), and oral vs topical terbinafine exposed (1:1). No significant differences in the risk of major malformations or spontaneous abortion between oral terbinafine-exposed, topical terbinafine-exposed, and unexposed pregnancies have been identified in propensity score–matched comparisons. Oral or topical use of terbinafine during pregnancy does not appear to be correlated with an increased risk of major malformations or spontaneous abortion.