Pregnancy represents a critical window during which obesity risk can be transmitted from one generation to the next. Maternal obesity and excessive gestational weight gain are associated with altered fetal development and an increased lifetime risk of obesity, diabetes, and cardiometabolic disease in offspring. Yet current models of antenatal care continue to rely largely on population-level recommendations, overlooking substantial variability in maternal physiology and metabolic health. Recent advances in our understanding of maternal energy metabolism offer an opportunity to reframe obesity prevention through a precision medicine lens. Evidence suggests that women with obesity have distinct energy requirements and metabolic adaptations during pregnancy, challenging longstanding assumptions regarding caloric needs and highlighting the limitations of a one-size-fits-all approach. These insights have informed the development of personalised gestational weight gain targets and tailored interventions designed to better align care with individual biological characteristics. This presentation will explore how precision approaches can be applied across the continuum of maternal and child health, drawing on clinical trials, digital health innovations, and mechanistic studies of maternal-fetal metabolism. Emerging research integrating metabolic phenotyping, body composition, placental biology, and infant metabolic function is beginning to identify the pathways through which the intrauterine environment influences lifelong susceptibility to obesity and metabolic disease. Preventing obesity may need to begin before birth. By moving beyond universal recommendations and towards biologically informed care, precision medicine has the potential to improve maternal health while modifying developmental trajectories that contribute to obesity risk across generations. Pregnancy may represent one of the greatest opportunities for precision prevention, offering the potential for lasting benefits for both mothers and their children.