Objective-To estimate the prevalence of anxiety disorders in pregnant and postpartum women and identify predictors accounting for variability across estimates. Data Sources-An electronic search of PsycINFO and PubMed was conducted from inception until July 2016, without date or language restrictions, and supplemented by articles referenced in the obtained sources. A Boolean search phrase utilized a combination of keywords related to pregnancy, postpartum, prevalence, and specific anxiety disorders.Study Selection-Articles reporting the prevalence of one or more of eight common anxiety disorders in pregnant or postpartum women were included. A total of 2,613 records were retrieved, with 26 studies ultimately included. Data Extraction-Anxiety disorder prevalence and potential predictor variables (e.g., parity) were extracted from each study. A Bayesian multivariate modeling approach estimated the prevalence and between-study heterogeneity of each disorder and the prevalence of having one or more disorder.Results-Individual disorder prevalence estimates ranged from 1.1% for PTSD to 4.8% for specific phobia, with the prevalence of having at least one or more disorder estimated to be 20.7%