Background: Gestational Diabetes Mellitus (GDM), once thought to be fully reversed after pregnancy, is now a firmly established independent risk factor for the subsequent development of Type 2 Diabetes Mellitus (T2DM), cardiovascular disease and other chronic conditions. This provides a strong rationale to identify preventive strategies in women with prior GDM, including intervention soon after childbirth. Currently, preventive strategies are mostly focused on modifying lifestyle, with an emphasis on diet and physical activity. However, evidence for the effectiveness of implementing and sustaining changes in behaviour through lifestyle programs is limited, and only a small proportion of women in Australia are thought to engage in lifestyle modification programs. Consideration of additional approaches, including pharmacotherapy, is therefore warranted. The current study aims to 1) measure the prevalence and identify the predictors (up to 4 years post-partum) of persisting dysglycaemia among a diverse population of urban Australian women with recent GDM, 2) understand women's views and views of their healthcare providers on long-term risks of T2DM and barriers and facilitators to engaging in screening and preventive strategies (including pharmacotherapy) to mitigate these risks, and 3) examine the feasibility of a randomised controlled trial of preventive drug therapies in this population. Methods: This is a retrospective cohort study with a qualitative sub-study. We will identify GDM-affected women who gave birth between January 2018 and December 2021 in at least three Sydney Hospitals (Liverpool Hospital, Royal Hospital for Women and St George Hospital) and invite them to participate in the study. Eligible participants will complete an online questionnaire and an oral glucose tolerance test to assess their current glycaemic status if they have not done so within 12 months of consent and are not currently pregnant. A subset of participants will be invited to participate in an interview to understand their perspectives of GDM, long-term risks and willingness to take preventive medications (including willingness to participate in trials of preventive medicines). Interviews with healthcare providers will also be conducted to understand their views of long-term diabetes risk, screening, and preventive strategies for women following GDM. Discussion: This study will help understand post-GDM care gaps and outcomes currently in Australia, as well as inform the design and conduct of future trials of preventive drug therapies in this population.