Cardiovascular disease (CVD) is a leading cause of death in low-, middle- and high-income countries, accounting for a quarter of deaths globally. This chapter examines what is currently known about maternal adiposity and gestational weight gain (GWG) and their associations with long-term of spring health, focusing on obesity and cardiovascular risk factors in offspring. It begins by summarizing the potential mechanisms that could explain the influence of maternal adiposity and GWG on offspring health. In support of the developmental over nutrition hypothesis, high concentrations of maternal glucose among those with gestational diabetes have been shown to increase nutrient transfer to the fetus and result in fetal hyperinsulinemia and increased fetal growth. Existing evidence suggests that intrauterine mechanisms are likely to result in long-term effects on offspring adiposity and cardiovascular risk factors among the extremely obese, in those with diabetes, and in association with greater amounts of GWG.