A population-based cohort study found that exposure to non-benzodiazepine sedative hypnotics (called Z-drugs) in the first trimester of pregnancy was not associated with an increased risk of birth defects.1 The study compared pregnant women exposed to Z-drugs with unexposed women and did not observe a significant increase in the overall risk of birth defects among exposed women.[1] The analyses also did not reveal an increased risk of major malformation subtypes that would suggest specific teratogenicity of Z-drugs when exposed early in development.1 The results provide reassuring data for the use of common sleeping medications beyond the first trimester, although the study focused specifically on Z-drugs and not all types of hypnotics.1][1] The authors emphasized that this was a population-based cohort; the main finding was the absence of an increased risk of congenital developmental defects with first-trimester exposure to Z-drugs[1].