: The long term impact of being born premature has received limited scientific investigation. Studies that have been carried out, focus on outcomes in childhood, with very few considering the impact on adult physical health. Three case studies are presented here, investigating differences in adult minor illness and psychological variables between adult participants born preterm, fullterm but small and fullterm with normal birthweight. This is a retrospective design using questionnaires and checklist to gather relevant information. Minor illness symptoms, daily hassles, anxiety, depression and general self-efficacy were measured. The participant born preterm scored higher on all measures. Data were applied to the Equilibrium Model for Minor Illness. Being born early appears to have a greater impact on later adult outcomes measured than being born fullterm but small or fullterm but of normal weight. In this article the authors reflect upon possible explanations for the different outcomes of each of the participants within the foetal origins of disease theory.