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Updated: Sep 6, 2026
Electrophysiological Measurements and Analysis of Nociception in Human Infants
Published on: December 20, 2011
Response to pain by different gestational age neonates
Chuanxiong Xia1, Lei Yang, Ping Zhao
1Department of Pediatrics, Xiehe Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022.
Insights
Full term infants exhibit more pronounced pain responses than premature infants. Differences in pain expression were also observed between premature infants of varying gestational ages (GA).
Area of Science:
- Neonatal care
- Developmental pediatrics
- Pain perception in infants
Background:
- Assessing pain in neonates is crucial for appropriate care.
- Premature infants may exhibit altered pain responses compared to full-term infants.
Purpose of the Study:
- To compare pain responses across different gestational age groups in infants.
- To identify specific behavioral indicators of pain in premature versus full-term neonates.
Main Methods:
- Infants were categorized into three groups based on gestational age: 29-32 weeks, 33-36 weeks, and full-term.
- Pain responses were evaluated through behavioral observations (cry, facial activity, limb movement) and heart rate monitoring.
Main Results:
- Significant differences in pain response intensity were observed among the three gestational age groups.
- Full-term infants displayed more pronounced pain behaviors than premature infants when exposed to identical stimuli.
- Specific facial expressions, such as vertical mouth stretch and taut tongue, were more common in full-term infants, while premature infants showed more horizontal mouth stretch.
Conclusions:
- Gestational age significantly influences an infant's pain response.
- Pain assessment protocols may need to account for maturational differences in neonates.
- Distinctive behavioral pain indicators exist between premature and full-term infants.
Abstract:
One hundred infants were divided into the following 3 gestational age (GA) groups: (I) premature infants (n = 30) with the gestational age between 29 and 32 weeks; (II) premature infants (n = 30) with the gestational age between 33 and 36 weeks; (III) full-term infants (n = 40). The recorded responses of all infants to pain included the behavioral responses to painful stimuli (cry, facial activity and limbs movement) and the variety of heart rate. The results indicated that the infants of 3 groups had different degree response to various painful stimuli. Pain expression in full term infants was more significant than premature infants to same stimuli. 33-weeks GA infants were differential from 29-weeks GA infants. Full term infants showed more vertical mouth stretch and more taut tongue and more hand to mouth than premature infants, but more horizontal mouth stretch in premature infants.
