Salivary Cortisol as Stress Marker in Newborns Subjected to Double Weighing With Physiological Body Weight

According to scientific revisions, salivary cortisol is a valid method for measuring adrenocortical activity in newborns because it is non-invasive in fact the measurement of salivary cortisol has been used as a stress marker in newborns since 1992. The mechanism by which cortisol induces stress, concerns the hypothalamic-pituitary-adrenal axis. The hypothalamus produces the corticotropin-releasing hormone, which stimulates the production of adrenocorticotropin by hypophysis. Adrenocorticotropin induces the secretion of glucocorticoids such as cortisol by stimulating the cortex of the adrenal gland. An appropriate release of cortisol due to stress factor is vital for surviving and the loss of this mechanism increase the risk of morbidity and mortality for newborns. However, prolonged exposure to a high level of cortisol may increase the risk of cognitive and behavioural disorders, hypertension, hyperlipidaemia, insulin resistance, immune deficiency and hippocampal impairment. The separation from the mother, the exposure to painful procedures but also routine interventions such as physical examination, diaper changes and bathing increase the salivary cortisol level of the newborn compared to the basal state. The measurement of salivary cortisol in the newborn therefore has the aim of understanding and preventing those stressful conditions that may have long-term side effects. For this reason, the lose weight in the first days and double weighing should be a stress practice for the newborn.