Endothelial progenitor cells (EPCs) are key regulators of vascular homeostasis in both health and disease, playing a crucial role in regenerating the human vascular lining throughout life. These circulating cells can differentiate into mature endothelial cells and are increasingly recognized as important biological markers of vascular function and cumulative risk for various diseases, including cardiovascular conditions. In recent decades, the role of EPCs, particularly the endothelial colony-forming cells (ECFCs) subtype, in pregnancy-related disorders and maternal and neonatal endothelial health has garnered significant attention. Evidence suggests that ECFCs may serve as predictor of future endothelial health in women and their offspring following pregnancy complications, making them particular relevant for research and therapeutic applications in adulthood, as well as potential indicators of vascular health. This review summarizes the evidence on EPCs, specifically ECFCs, as biomarkers of endothelial health in pregnancy, pregnancy-related diseases and ageing, with a focus on maternal and foetal endothelial abnormalities that may serve as prognostic factors for the development of future diseases.