Total body water in full-term and preterm newborns: systematic review and meta-analysis.
Level 2 - randomized trial
Systematic review and meta-analysis of observational studies (by design analogy, not randomized trials)
PubMed 33789970 · doi:10.1136/archdischild-2020-321112
What was done
A systematic review and meta-analysis of Medline, Web of Science Core Collection, and EBSCO-CINAHL (January 1946 to January 2020) evaluating percentage of total body water (TBW) in term and preterm infants assessed via dilutional methods. Meta-regression was used to quantify the effect of gestational age at birth on TBW.
What was found
From 2,349 identified articles, 22 were included in the analysis: - Mean TBW in term-born newborns was 73.8% (95% CI 72.47% to 75.06%; 15 studies, 433 infants). - TBW reached up to 90% at 26 weeks gestation and dropped to 75% at 36 weeks corrected gestation. - TBW was negatively correlated with gestational age at birth, falling 1.44% per week (95% CI 0.63% to 2.24%; 9 studies, 179 infants). - Progression of TBW over time during ex utero growth in preterm infants could not be analyzed due to insufficient data.
Why it matters
It provides benchmark reference ranges for neonatal total body water and quantifies the rate of TBW decline with advancing gestational age, informing fluid and nutritional management.
Limits
Total participant numbers across decades of literature are relatively small (433 term and 179 preterm infants in the main quantitative syntheses). Data were inadequate to assess longitudinal changes in TBW during ex utero growth.
Cited by
- contradicts Water makes up 85 to 90% of cells and the human body.