Long-term alterations in pain sensitivity following preterm birth: a systematic review and meta-analysis

Area of Science:

• Neonatal care and developmental neuroscience
• Pain research and somatosensory processing
• Longitudinal health outcomes in vulnerable populations

Background:

• Preterm infants endure frequent painful procedures, raising concerns about lasting impacts on pain processing.
• Existing evidence on long-term pain sensitivity in preterm individuals is inconsistent.
• Understanding these long-term effects is crucial for optimizing neonatal care and support.

Purpose of the Study:

• To synthesize long-term evidence on pain sensitivity in individuals born preterm versus term.
• To investigate differences in thermal and mechanical pain thresholds and pain intensity from childhood to young adulthood.

Main Methods:

• Systematic literature search of major databases (PubMed, Cochrane, Web of Science, Scopus) up to September 2025.
• Inclusion of observational studies with preterm and term-born participants aged 7-28 years.
• Meta-analysis of quantitative sensory testing (QST) and self-reported pain intensity, with heterogeneity assessment.

Main Results:

• Analysis of 8 studies (731 participants) revealed preterm-born individuals reported higher pain intensity (SMD=0.45, p=0.03).
• Preterm-born participants exhibited higher heat pain thresholds (MD=1.11°C, p=0.002) compared to term-born.
• No significant differences were found for other QST outcomes; substantial heterogeneity was noted in several analyses.

Conclusions:

• Preterm birth is associated with altered pain sensitivity, specifically higher heat pain thresholds and pain intensity ratings in later life.
• Findings highlight the need for further well-designed longitudinal studies to refine neonatal pain management strategies.
• Standardized protocols in future research are essential for clearer insights into pain processing differences.