Preterm Infant Incubator Humidity Levels: A Systematic Review

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Advanced Neonatal Care

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Downloads before May 2022



Background: Numerous scholars have reported that inconsistent levels of incubator humidity in the neonatal intensive care unit (NICU) require attention. Evidence synthesis was needed to identify optimal incubator humidity levels and duration to decrease transepidermal water loss (TEWL) and the potential for infection.

Purpose: The purpose of this systematic review was to appraise and synthesize the evidence of preterm outcomes related to incubator humidity. The primary aim of this study was to determine how patient outcomes were impacted by incubator humidity levels and duration in premature infants born before 320/7 weeks cared for in the NICU.

Methods/search strategy: The foundation of this systematic review was the Joanna Briggs Institute method for systematic reviews. Mefford's theory of health promotion for the preterm infant was used to address the wholeness of the preterm infant's body system. Evidence was classified using the Johns Hopkins evidence-based practice levels and quality of evidence.

Findings: Twelve studies met inclusion criteria. The evidence demonstrated that the practice of incubator humidity is warranted; however, it does not come without risks. Microbial growth was increased in high levels of incubator humidity. Unnecessary TEWL was prevented by lowering high levels of incubator humidity after the first week of life, improving skin barrier formation.

Implications for practice: Incubator humidity of 60% to 70% in the first week of life was effective in preventing TEWL in infants born 26 weeks or more.

Implications for research: Future incubator humidity research is needed for infants born before 26 weeks.Video Abstract available at