Skin thickness dimensions in histological section measurement during late-fetal and neonatal developmental period: A systematic review

Background The development and maturation of the skin is a process that occurs during the gestation and neonatal period. Histological skin biopsy studies are relevant to improve knowledge on the skin protective barrier during the perinatal period. The thin skin of preterm newborns is unable to maintain homeostasis, thermal regulation through the skin, and is susceptible to infections. This study systematically reviewed the evidence regarding histological thickness dimensions of the skin and its layers during the late-fetal and neonatal period. Methods PubMed, Scopus, BVS, and e SciELO library databases, with no limits in the period of analysis or idiom. Eligibility criteria were as follows: studies describing the thickness of the entire skin or its layers during late-fetal life or the neonatal period; human being; skin biopsy analysis; and any scientific report. Two independent reviewers screened the search and extracted the following standard data: fetal or neonatal age of assessment, biopsy site, technique used for preparation and staining of histological slides, measurement techniques, and values of skin thickness. Results Fifty-nine studies were screened, and eleven were identified from other sources. We recognized six studies that met the criteria for inclusion for proper extraction. Expressive differences between sites for sampling, methods of slide preparation, and number of layers measured made the thicknesses values summarization difficult. There were no reliable dimensions reported on this tissue. Conclusion Despite the importance of studying the human skin barrier, these findings confirmed limited evidence on skin thickness dimensions obtained by histology.