The questionnaires will be self-administered in the home (NHS-II participants).You may complete the questionnaire online using the web site address (i.e., URL), username and password provided in the invitation letter and/or by site staff. Alternatively, scannable paper forms may be provided if preferred. In either case, your responses to the questionnaire will be secure and anonymous, and no identifiable information will be present. The questionnaire will collect data pertaining to your general information (i.e., age, gender, race, employment, etc.), health conditions, pregnancy history, first pregnancy affected by GDM, sleeping ability, body shape and other body characteristics, and physical activity. Women from Denmark will also complete a questionnaire about the foods they eat. All of this information is necessary in order to fully evaluate the many lifestyle and health factors that could influence the development of type 2 diabetes in women with a previous history of GDM. Your care and attention to providing complete and accurate information will assist the study team in analyzing the collected data and deriving reliable predictors of type 2 diabetes.