Problem/background: Pregnancy-related anxiety is a distinct anxiety characterised by pregnancy-specific concerns. This anxiety is consistently associated with adverse birth outcomes, and obstetric and paediatric risk factors, associations generally not seen with other anxieties. The need exists for a psychometrically sound scale for this anxiety type. This study, therefore, reports on the initial development of the Pregnancy-related Anxiety Scale. Methods: The item pool was developed following a literature review and the formulation of a definition for pregnancy-related anxiety. An Expert Review Panel reviewed the definition, item pool and test specifications. Pregnant women were recruited online (N = 671). Results: Using a subsample (N = 262, M = 27.94, SD = 4.99), fourteen factors were extracted using Principal Components Analysis accounting for 63.18% of the variance. Further refinement resulted in 11 distinct factors. Confirmatory Factor Analysis further tested the model with a second subsample (N = 369, M = 26.59, SD = 4.76). After additional refinement, the resulting model was a good fit with nine factors (childbirth, appearance, attitudes towards childbirth, motherhood, acceptance, anxiety, medical, avoidance, and baby concerns). Internal consistency reliability was good with the majority of subscales exceeding α = .80. Conclusions: The Pregnancy-related Anxiety Scale is easy to administer with higher scores indicative of greater pregnancy-related anxiety. The inclusion of reverse-scored items is a potential limitation with poorer reliability evident for these factors. Although still in its development stage, the Pregnancy-related Anxiety Scale will eventually be useful both clinically (affording early intervention) and in research settings.