Pain reactivity in preterm neonates: examining the sex differences

Area of Science:

• Neonatal care
• Pain research
• Developmental pediatrics

Background:

• Neonatal Intensive Care Unit (NICU) hospitalizations expose vulnerable newborns to early and repeated pain.
• Neonatal pain responses are influenced by various factors encountered by neonates.

Purpose of the Study:

• To test the hypothesis that male preterm neonates exhibit greater pain sensitivity than females.
• To assess biobehavioral pain reactivity and recovery patterns in response to painful procedures.

Main Methods:

• Observed 53 preterm, low birthweight infants in the NICU across five phases: baseline, antisepsis, puncture, recovery-dressing, and recovery-resting.
• Measured behavioral pain reactivity using the Neonatal Facial Coding System (NFCS) and Sleep-Wake States Scale (SWS).
• Continuously recorded heart rate (HR) and assessed scores and magnitude of responses.

Main Results:

• No statistical differences were found between male and female preterm neonates in NFCS and SWS scores, indicating similar behavioral pain reactivity and recovery patterns.
• Male preterm infants showed higher HR during the initial minute of the puncture phase compared to females.
• Male preterm infants exhibited a greater change in maximum HR from baseline to puncture phase than female preterm infants.

Conclusions:

• While male infants demonstrated higher physiological reactivity (HR parameters) to painful stimuli than females, the findings were insufficient to confirm sex influence on biobehavioral pain response in vulnerable neonates.
• Further research is needed to fully elucidate the role of sex in neonatal pain perception and response.