The menopausal transition (MT) are natural processes that occur in women’s lives as part of normal aging and includes the period of change from perimenopause to postmenopause and its associated symptoms. Weight and body fat distribution change particularly during menopausal transition is commonly reported. Although extensive international research has been conducted, the links between weight variation, body composition, shape and the menopause transition are complex and not extensively understood. Nationally there is a sparsity of data regarding the menopausal transition regarding body shape, body composition and weight. Findings from international research suggest health behaviours (including diet and physical activity) and the prevention of certain health conditions (including obesity) are key targets to ensure midlife women who encounter challenges related to MT, maintain optimal health and wellbeing as they age. This PhD focuses on a highly unexplored area of research in Ireland- exploration of weight variation, body composition and body shape in Irish women during the menopause transition. This will have the potential to provide a unique and significant understanding of this stage in women’s life and will inform future interventions and policy in the Irish context.