There is a large population of children conceived via assisted reproductive technology (ART), which continues to increase worldwide, without a clear understanding of associated long-term outcomes. ART children are more likely to be the result of multiple pregnancies, and thus to be born prematurely or low birthweight. There is growing evidence that ART children are phenotypically and biochemically different from naturally conceived children, but the mechanism(s) leading to these changes have not been elucidated. There is a possible increased risk of rare imprinted gene disorders in these children. However, it remains unclear whether more subtle changes in DNA methylation occur commonly, leading to differences in gene expression and phenotype in ART children. Although an increased risk of cancer among ART children has been reported, the role of ART in the development of cancer has not been demonstrated. Further research and ongoing surveillance of ART children is essential to better understand the possible effects of ART on the long-term health of this population.