Yonsei Med J.  2011 Jan;52(1):98-103. 10.3349/ymj.2011.52.1.98.

Stress Responses of Neonates Related to Maternal Characteristics

• Joung KH
• Cho SC

• KMID: 1106443
• DOI: http://doi.org/10.3349/ymj.2011.52.1.98

Abstract

PURPOSE
To investigate the pre- and post-heelstick stress response patterns of infants and to identify related maternal factors.
MATERIALS AND METHODS
Fifty-two mothers and their 57 infants were studied. Stress response patterns in neonates were collected by measurements of pulse rate, oxygen saturation, and salivary cortisol. Maternal demographic factors and awakening saliva were collected.
RESULTS
Median level of pulse rate of infant increased from 132.1 to 140.4 beats per minute and salivary cortisol was elevated from 0.41 microg/dL to 0.70 microg/dL during the periods of discomfort, while oxygen saturation decreased from 97% to 95%. Infant's pulse rate change was negatively correlated with gestational age (GA) (r = - 0.37, p < 0.05), whereas the change of infants' salivary cortisol was correlated positively with maternal age (r = 0.29, p < 0.05). GA was the only independently significant predictor of pulse rate responses (R2 = 0.15, p < 0.05). Influence of maternal age on infants' salivary cortisol changes (R2 = 0.09, p < 0.05) was observed in a stepwise multiple regression.
CONCLUSION
These findings suggest that maternal age and gestational period can be influential factors for stress responses in infants. Therefore, it would be important to consider the demographic characteristics of mother-infant pairs to evaluate these influential factors.

Keyword

Stress response; saliva; cortisol; gestational age; maternal age

MeSH Terms

Adult
Female
Gestational Age
Heart Rate/physiology
Humans
Hydrocortisone/analysis
Infant, Newborn
Male
Maternal Age
Mothers
Pregnancy
Saliva/chemistry
Stress, Physiological/*physiology

Figure

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  Fig. 1 Summary of recruitment procedure.

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  Fig. 2 Pulse rate, oxygen saturation, and salivary cortisol changes of infants to heelstick.

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