Abstract
A number of models of behaviour have been applied to contraception use including subjective expected utility theory and social cognition models. Whilst correlates of contraception use have been identified, the limitations of these models include their failure to consider either contextual factors or changes in contraception use over time. Researchers have called for integrated and dynamic models of contraception use, which can be related to the changing contraception use of individual women and can also be readily operationalised to explore within and between subject differences in contraception use. The present study therefore used a qualitative methodology to explore women's contraceptive histories and to enable women to define the issues from their perspectives, resulting in a model of contraception use that is firmly located within the context of their own lives and allows an investigation of the factors and processes involved in changes in contraception use/ non-use over time. This model conceptualises the predictors of contraception use in terms of the meaning and importance of a range of social goals, perceptions of vulnerability and constraints on or facilitators of contraception. Further the dynamic nature of these factors is described and it is illustrated how these core components vary over time according to situation, experience, and new information. The paper outlines the relevance of the findings for different models of decision-making processes and highlights the way that the model addresses the limitations of previous approaches.