Women who have diabetes during pregnancy have more complicated pregnancies and deliveries and are at risk of later metabolic disease. It appears that their children are also at a higher risk for obesity and diabetes, but the exact cause is not clear. Our proposed main study is a retrospective cohort study of Wellington women with diabetes during pregnancy, from 1981 to 2002. We aim to determine whether metabolic disease in their children is due to increased glucose in their blood during pregnancy; or obesity, family history and social environment. All women and their families, and a matched control group, will be invited to undertake investigations assessing their risks for obesity, diabetes and heart disease. This feasibility study will determine rates and strategies for recruitment, particularly for Maori and Pacific families. These groups have clear disparities in metabolic disease during and after pregnancy and may therefore benefit substantially from targeted interventions.