title: Repeated antenatal corticosteroid treatment: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To systematically review the efficacy and safety of repeated antenatal corticosteroid on neonatal morbidity, growth and later development.
  
  
  METHODS
  MEDLINE, Cochrane database and a bibliography of identified articles were searched for English language studies. Design. Meta-analysis of randomized controlled trials.
  
  
  METHODS
  Randomized, controlled trials studying the efficacy and safety of repeat antenatal corticosteroid treatment on neonatal morbidity and early childhood development.
  
  
  METHODS
  Respiratory distress syndrome, intrauterine growth, neurodevelopment.
  
  
  METHODS
  Two reviewers independently assessed titles, abstracts and full studies, extracted data and assessed quality. Meta-analyses were performed, calculating risk ratios and weighted differences of means with 95% confidence intervals using a random-effects model.
  
  
  RESULTS
  Eight trials were included. Repeated betamethasone treatment decreased the risk of respiratory distress syndrome (relative risk 0.85, 95% confidence interval 0.77-0.93). Trials involving weekly or biweekly repeated betamethasone and those involving a single rescue dose decreased the risk of respiratory distress syndrome. Intrauterine growth was significantly restricted among preterm infants exposed to weekly or biweekly repeated betamethasone. A single rescue course did not affect growth. Four follow-up studies did not reveal any disturbances in neurodevelopment or growth at two years of corrected age.
  
  
  CONCLUSIONS
  Repeated corticosteroid treatment decreased the risk of respiratory distress syndrome among preterm infants. Weekly or biweekly repeated betamethasone restricted intrauterine growth, which raises concerns about long-term consequences on neurodevelopment and metabolism. More follow-up studies are needed to confirm the long-term safety of repeated betamethasone.
authors.affiliation: Department of Pediatrics, University of Oulu, Finland. outi.peltoniemi@mail.suomi.net
authors.forename: Outi M
authors.initials: OM
authors.lastname: Peltoniemi
authors.forename: M Anneli
authors.initials: MA
authors.lastname: Kari
authors.forename: Mikko
authors.initials: M
authors.lastname: Hallman
mesh_terms: D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects*; D001623:Betamethasone / Q000008:administration & dosage / Q000009:adverse effects*; D002657:Child Development / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D047109:Fetal Development / Q000187:drug effects; D005387:Finland; D006801:Humans; D015994:Incidence; D007226:Infant Mortality / Q000639:trends; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000517:prevention & control*; D011295:Prenatal Care / Q000379:methods; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D015996:Survival Rate
chemical_list: D000305:Adrenal Cortex Hormones; D001623:Betamethasone