[GESTASTRES cohort study protocol on the effects of stress during pregnancy by measuring the cortisol in women's and newborn's hair].

The aim was to present the longitudinal study protocol on the effects of perinatal stress from conception to one year of age. Stress is associated to psychopathological, cardiovascular and inmunological diseases. During pregnancy, the activation of the Hipotalamic-Pituitary-Adrenal results in an increased release of cortisol. Stress during pregnancy is related to maternal, fetal and infant negative outcomes that can last a lifetime. Nevertheless, contradictory findings have been reported. In this longitudinal study maternal stress is assessed from a sample of 807 pregnant women through hair cortisol levels and psychological question- naires during the three trimesters of pregnancy. Besides, associa- tions with the new-borns´ hair cortisol levels, temperament and neurodevelopment at age 6 and 12 months are assessed. Sociode- mographic, obstetrics, delivery, fetal and newborn development variables are included in analysis. Findings will be able to pro- vide a better understanding of perinatal stress and will improve maternal, fetal and infant outcomes.