The gradual fall in birth and death rates, over the past decades, have resulted in demographic changes that are characterised by low fertility and high life expectancy. As a result, the number of older people in Europe is rapidly increasing and The World Health Organization reports the median age of the European population as the highest in the world and predicts that the proportion of over-60s in the WHO European Region will increase from 14% in 2010 to 25% in 2050. However, there is wide variability in the quality of health and well-being in the ageing population. Longevity with a good quality of life is a consequence of the combination of an individual's genes, nutrition, environment, lifestyle and medical interventions. There is increasing evidence that research into healthy ageing needs to start with data from the early life to capture all traits and exposures experienced by an individual throughout life. Epigenetic imprinting occurs both in utero and during early postnatal development. Maternal environmental exposures, including nutritional status, may have a permanent effect on the developing foetus by influencing epigenetic profiles and leading to life-long genome adaptation. Numerous reports show that restricted intra-uterine growth due to poor maternal nutrition during pregnancy increases risk in the offspring of developing mental disorders, metabolic syndrome, cardiovascular disease or stroke in later life. To understand the basic mechanisms and interactions through which the ageing phenotype develops, systems involved in key processes of early development must be considered as well as those crucial to health in older persons. The Reus and Tarragona Birth Cohort is a longitudinal study. In the first phase, blood is collected from pregnant women at <12, 15, 24-27 and 34 gestational weeks (GW)and at labor and from the cord. Detailed lifestyle, habits and supplement use data are collected at 20 and 32 gestational weeks and on nutritional habits at <12GW and at birth. Placental vascular function is assessed at 20 and 32 GW by analysis of Doppler waveforms of the uterine arteries. Data on pregnancy evolution and outcome are also recorded. This first phase investigated the association between gene-environment (nutrient and lifestyle habits) interactions and fetal growth and pregnancy outcome. The upcoming second phase of this study will follow up the children at 7.5 years of age. Growth, exercise and nutritional habits as well as environment and cognitive development will be assessed. The aims are to investigate the association between gene-environment interactions associated with healthy development from early pregnancy until 7.5 years of age.