Early origins of adult disease may be defined as adversity or challenges during early life that alter physiological responses and prime the organism to chronic disease in adult life. Adverse childhood experiences or early life stress (ELS) may be considered a silent independent risk factor capable of predicting future cardiovascular disease risk. Maternal separation (MatSep) provides a suitable model to elucidate the underlying molecular mechanisms by which ELS increases the risk to develop cardiovascular disease in adulthood. The aim of this review is to describe the links between behavioural stress early in life and chronic cardiovascular disease risk in adulthood. We will discuss the following: (i) adult cardiovascular outcomes in humans subjected to ELS, (ii) MatSep as an animal model of ELS as well as the limitations and advantages of this model in rodents and (iii) possible ELS-induced mechanisms that predispose individuals to greater cardiovascular risk. Overall, exposure to a behavioural stressor early in life sensitizes the response to a second stressor later in life, thus unmasking an exaggerated cardiovascular dysfunction that may influence quality of life and life expectancy in adulthood. © 2013 Scandinavian Physiological Society.