Cortisol Analysis Using a Novel Method of Saliva Collection: Method and Application in Preterm Infants

= 31) using flocked polyester swabs to measure HPA responses to routine, clustered nursing care. Saliva samples were collected from each infant prior to caregiving, 30-min after caregiving, and 60-min after caregiving. Aliquots from the same adult were highly correlated. Sufficient volumes of saliva were extracted from 91 of 93 infant swabs (98%). Changes in cortisol levels from baseline to 30-min and 60-min after caregiving were negatively associated with acute procedural stress, quantified using the Neonatal Infant Stressor Scale. The change in cortisol level from baseline to 60-min after caregiving was negatively associated with caregiving duration. Further research is needed to understand the relationship between caregiving stress exposure and HPA axis responses in preterm infants and to identify the myriad factors that may influence this association. Flocked polyester swabs offer a viable option for the collection of sufficient volumes of saliva to support this research.