Late prematurity: a systematic review

J Pediatr (Rio J). 2014 May-Jun;90(3):221-31. doi: 10.1016/j.jped.2013.08.012. Epub 2014 Feb 6.

Abstract

Objective: this study aimed to review the literature regarding late preterm births (34 weeks to 36 weeks and 6 days of gestation) in its several aspects.

Sources: the MEDLINE, LILACS, and Cochrane Library databases were searched, and the references of the articles retrieved were also used, with no limit of time.

Data synthesis: numerous studies showed a recent increase in late preterm births. In all series, late preterm comprised the majority of preterm births. Studies including millions of births showed a strong association between late preterm birth and neonatal mortality. A higher mortality in childhood and among young adults was also observed. Many studies found an association with several neonatal complications, and also with long-term disorders and sequelae: breastfeeding problems, cerebral palsy, asthma in childhood, poor school performance, schizophrenia, and young adult diabetes. Some authors propose strategies to reduce late preterm birth, or to improve neonatal outcome: use of antenatal corticosteroids, changes in some of the guidelines for early delivery in high-risk pregnancies, and changes in neonatal care for this group.

Conclusions: numerous studies show greater mortality and morbidity in late preterm infants compared with term infants, in addition to long-term disorders. More recent studies evaluated strategies to improve the outcomes of these neonates. Further studies on these strategies are needed.

Keywords: Early neonatal mortality; Gravidez de alto risco; High-risk pregnancy; Infant mortality; Mortalidade infantil; Mortalidade neonatal; Mortalidade neonatal precoce; Neonatal mortality; Preterm labor; Trabalho de parto prematuro.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Adult
  • Child
  • Child, Preschool
  • Female
  • Fetal Organ Maturity
  • Gestational Age
  • Humans
  • Incidence
  • Infant
  • Infant Mortality / trends*
  • Infant, Newborn
  • Infant, Premature*
  • Infant, Premature, Diseases / mortality*
  • Lung / embryology
  • Pregnancy
  • Premature Birth / epidemiology*
  • Time Factors
  • Young Adult