The purpose of the study was to examine the stability of the adrenocortical response to stimulation in the human neonate. Forty-nine healthy newborns were examined twice responding to discharge examinations performed on two consecutive days. The dependent measures were salivary and plasma cortisol and behavioral state. Little evidence of stability was obtained. Instead, the results showed significant elevations in cortisol only in response to the first discharge examination. No significant elevation in cortisol was noted to the second discharge examination although the newborns continued to exhibit behavioral distress. Time since delivery was not a significant factor in producing these results. The findings are discussed with regard to neonatal coping processes and the importance of novelty in regulating increases in adrenocortical activity.

The association between behavioral distress and adrenocortical activity was examined in two experiments with human newborns. In Experiment 1, behavioral and adrenocortical responses to 4 events (circumcision, blood sampling, weighing and measuring, and discharge examination) were compared using a between-subject design. All 4 events elicited fussing and crying and elevations in plasma cortisol; however, differences in behavioral distress among conditions did not reliably predict differences in plasma cortisol. In Experiment 2, nonnutritive sucking was used to effectively reduce behavioral distress, but was not associated with a reduction in the adrenocortical response to stimulation. Finally, using data from both experiments, correlations were computed between behavioral distress and cortisol. Both positive and negative associations were found as a function of the type of stressor and the biomedical status of the newborn.