Am J Perinatol
DOI: 10.1055/s-0043-1776344
Review Article

A Scoping Review of the Oral Microbiome in Preterm Infants

1   Department of Biobehavioral Nursing Science, College of Nursing, University of Florida, Gainesville, Florida
Marion M. Bendixen
2   Department of Family, Community and Health System Science, University of Florida, Gainesville, Florida
Angela Monk
1   Department of Biobehavioral Nursing Science, College of Nursing, University of Florida, Gainesville, Florida
Monica F.T. Lamberti
3   Department of Microbiology and Cell Science University of Florida, Microbiology and Cell Science, Gainesville, Florida
Graciela L. Lorca
3   Department of Microbiology and Cell Science University of Florida, Microbiology and Cell Science, Gainesville, Florida
Josef Neu
4   Department of Pediatrics, College of Medicine, University of Florida, Gainesville, Florida
Leslie A. Parker
1   Department of Biobehavioral Nursing Science, College of Nursing, University of Florida, Gainesville, Florida
› Author Affiliations


The purpose of this scoping review was to examine the oral microbiome composition in preterm infants, sampling and collection methods, as well as exposures associated with oral microbiome composition and health implications. We conducted a scoping review of the literature using the Arskey and O'Malley framework. We identified a total of 13 articles which met our inclusion criteria and purpose of this scoping review. Articles included in this review compared the oral microbiome in preterm infants to term infants, examined alterations to the oral microbiome over time, compared the oral microbiome to different body site microbiomes, and explored associations with clinically relevant covariates and outcomes. Exposures associated with the diversity and composition of the oral microbiome in preterm infants included delivery mode, oral feeding, oropharyngeal care, skin-to-skin care, and antibiotics. Day of life and birth weight were also associated with oral microbiome composition. The oral microbiome may be associated with the composition of the tracheal and gut microbiomes, likely due to their proximity. Alpha and beta diversity findings varied across studies as well as the relative abundance of taxa. This is likely due to the different sampling techniques and timing of collection, as well as the wide range of infant clinical characteristics. Multiple factors may influence the composition of the oral microbiome in preterm infants. However, given the heterogeneity of sampling techniques and results within this review, the evidence is not conclusive on the development as well as short- and long-term implications of the oral microbiome in preterm infants and needs to be explored in future research studies.

Key Points

  • Day of life is a critical factor in oral microbiome development in preterm infants.

  • The oral microbiome may be associated with tracheal and gut microbiome colonization.

  • Future research should examine sampling methodology for examining the oral microbiome.

  • Future research should explore associations with the oral microbiome and adverse health outcomes.

Supplementary Material

Publication History

Received: 01 June 2023

Accepted: 28 September 2023

Article published online:
31 October 2023

© 2023. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

  • References

  • 1 Robertson RC, Manges AR, Finlay BB, Prendergast AJ. The human microbiome and child growth - first 1000 days and beyond. Trends Microbiol 2019; 27 (02) 131-147
  • 2 Lee YH, Chung SW, Auh QS. et al. Progress in oral microbiome related to oral and systemic diseases: an update. Diagnostics (Basel) 2021; 11 (07) 1283
  • 3 Xiao J, Fiscella KA, Gill SR. Oral microbiome: possible harbinger for children's health. Int J Oral Sci 2020; 12 (01) 12
  • 4 Antoine J, Inglis GDT, Way M, O'Rourke P, Davies MW. Bacterial colonisation of the endotracheal tube in ventilated very preterm neonates: a retrospective cohort study. J Paediatr Child Health 2020; 56 (10) 1607-1612
  • 5 Vongbhavit K, Salinero LK, Kalanetra KM. et al. A comparison of bacterial colonization between nasogastric and orogastric enteral feeding tubes in infants in the neonatal intensive care unit. J Perinatol 2022; 42 (11) 1446-1452
  • 6 Groer MW, Miller EM, D'Agata A. et al. Contributors to dysbiosis in very-low-birth-weight infants. J Obstet Gynecol Neonatal Nurs 2020; 49 (03) 232-242
  • 7 Bhatta DR, Hosuru Subramanya S, Hamal D. et al. Bacterial contamination of neonatal intensive care units: how safe are the neonates?. Antimicrob Resist Infect Control 2021; 10 (01) 26
  • 8 Thänert R, Keen EC, Dantas G, Warner BB, Tarr PI. Necrotizing enterocolitis and the microbiome: current status and future directions. J Infect Dis 2021; 223 (12, Suppl 2) S257-S263
  • 9 Pammi M, Lal CV, Wagner BD. et al. Airway microbiome and development of bronchopulmonary dysplasia in preterm infants: a systematic review. J Pediatr 2019; 204: 126-133.e2
  • 10 Yusef D, Shalakhti T, Awad S, Algharaibeh H, Khasawneh W. Clinical characteristics and epidemiology of sepsis in the neonatal intensive care unit in the era of multi-drug resistant organisms: a retrospective review. Pediatr Neonatol 2018; 59 (01) 35-41
  • 11 Bell EF, Hintz SR, Hansen NI. et al; Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Mortality, in-hospital morbidity, care practices, and 2-year outcomes for extremely preterm infants in the us, 2013–2018. JAMA 2022; 327 (03) 248-263
  • 12 Brewer MR, Maffei D, Cerise J. et al. Determinants of the lung microbiome in intubated premature infants at risk for bronchopulmonary dysplasia. J Matern Fetal Neonatal Med 2021; 34 (19) 3220-3226
  • 13 Biagi E, Aceti A, Quercia S. et al. Microbial community dynamics in mother's milk and infant's mouth and gut in moderately preterm infants. Front Microbiol 2018; 9: 2512
  • 14 Young GR, van der Gast CJ, Smith DL, Berrington JE, Embleton ND, Lanyon C. Acquisition and development of the extremely preterm infant microbiota across multiple anatomical sites. J Pediatr Gastroenterol Nutr 2020; 70 (01) 12-19
  • 15 Arksey H, O'Malley L. Scoping studies: towards a methodological framework. Int J Soc Res Methodol 2005; 8 (01) 19-32
  • 16 Costello EK, Carlisle EM, Bik EM, Morowitz MJ, Relman DA. Microbiome assembly across multiple body sites in low-birthweight infants. MBio 2013; 4 (06) e00782-e13
  • 17 Cortez RV, Fernandes A, Sparvoli LG. et al. Impact of oropharyngeal administration of colostrum in preterm newborns' oral microbiome. Nutrients 2021; 13 (12) 4224
  • 18 Hendricks-Muñoz KD, Xu J, Parikh HI. et al. Skin-to-skin care and the development of the preterm infant oral microbiome. Am J Perinatol 2015; 32 (13) 1205-1216
  • 19 Li H, Zhang Y, Xiao B, Xiao S, Wu J, Huang W. Impacts of delivery mode on very low birth weight infants' oral microbiome. Pediatr Neonatol 2020; 61 (02) 201-209
  • 20 Orchanian SB, Gauglitz JM, Wandro S. et al. Multiomic analyses of nascent preterm infant microbiomes differentiation suggest opportunities for targeted intervention. Adv Biol 2022; 6 (08) e2101313
  • 21 Sohn K, Kalanetra KM, Mills DA, Underwood MA. Buccal administration of human colostrum: impact on the oral microbiota of premature infants. J Perinatol 2016; 36 (02) 106-111
  • 22 Zioutis C, Seki D, Bauchinger F. et al. Ecological processes shaping microbiomes of extremely low birthweight infants. Front Microbiol 2022; 13: 812136
  • 23 Romano-Keeler J, Azcarate-Peril MA, Weitkamp JH. et al. Oral colostrum priming shortens hospitalization without changing the immunomicrobial milieu. J Perinatol 2017; 37 (01) 36-41
  • 24 Younge NE, Araújo-Pérez F, Brandon D, Seed PC. Early-life skin microbiota in hospitalized preterm and full-term infants. Microbiome 2018; 6 (01) 98
  • 25 Li D, Huang Y, Sadykova A. et al. Composition of the microbial communities at different body sites in women with preterm birth and their newborns. Med Microecol 2021; 9: 100046
  • 26 Kaan AMM, Kahharova D, Zaura E. Acquisition and establishment of the oral microbiota. Periodontol 2000 2021; 86 (01) 123-141
  • 27 Seki D, Mayer M, Hausmann B. et al. Aberrant gut-microbiota-immune-brain axis development in premature neonates with brain damage. Cell Host Microbe 2021; 29 (10) 1558-1572.e6
  • 28 Petersen SM, Greisen G, Krogfelt KA. Nasogastric feeding tubes from a neonatal department yield high concentrations of potentially pathogenic bacteria- even 1 d after insertion. Pediatr Res 2016; 80 (03) 395-400
  • 29 Perkins SD, Woeltje KF, Angenent LT. Endotracheal tube biofilm inoculation of oral flora and subsequent colonization of opportunistic pathogens. Int J Med Microbiol 2010; 300 (07) 503-511
  • 30 Parker LA, Pruitt J, Monk A, Lambert MT, Lorca GL, Neu J. Oral care in critically ill infants and the potential effect on infant health: an integrative review. Crit Care Nurse 2023; 43 (04) 39-50
  • 31 Ma A, Yang J, Li Y, Zhang X, Kang Y. Oropharyngeal colostrum therapy reduces the incidence of ventilator-associated pneumonia in very low birth weight infants: a systematic review and meta-analysis. Pediatr Res 2021; 89 (01) 54-62
  • 32 Tao J, Mao J, Yang J, Su Y. Effects of oropharyngeal administration of colostrum on the incidence of necrotizing enterocolitis, late-onset sepsis, and death in preterm infants: a meta-analysis of RCTs. Eur J Clin Nutr 2020; 74 (08) 1122-1131
  • 33 Ballard O, Morrow AL. Human milk composition: nutrients and bioactive factors. Pediatr Clin North Am 2013; 60 (01) 49-74
  • 34 Cabrera-Rubio R, Collado MC, Laitinen K, Salminen S, Isolauri E, Mira A. The human milk microbiome changes over lactation and is shaped by maternal weight and mode of delivery. Am J Clin Nutr 2012; 96 (03) 544-551