title: Cardiovascular responses to maternal betamethasone administration in the intrauterine growth-restricted ovine fetus.
abstract: OBJECTIVE
  The objective was to characterize the effect of glucocorticoid treatment on fetal organ blood flow and regional cerebral blood flow in normally grown fetuses and fetuses with intrauterine fetal growth restriction (IUGR).
  
  
  METHODS
  Studies were undertaken in both control and IUGR fetal sheep; growth restriction was induced by ligation of 1 umbilical artery. Fetuses received colored microspheres for organ blood flow calculations before and after 2 maternal betamethasone injections (BM1 and BM2).
  
  
  RESULTS
  Following BM1, cardiac output was significantly decreased in the control fetuses and blood flow to the heart and placenta was unchanged, whereas total cerebral blood flow was significantly decreased (P<.001), consistent with cerebral vasoconstriction. In the fetuses with IUGR, the cardiac output was significantly increased at +33 hours relative to BM1, and blood flow was increased in all organs; notably, there was a 2-fold increase in cerebral blood flow (P=.03).
  
  
  CONCLUSIONS
  The cardiovascular response of the fetus with IUGR to glucocorticoids is profoundly different from the control fetuses, which may induce both short- and long-term injury.
authors.affiliation: Department of Obstetrics and Gynecology, Monash Institute of Medical Research, Monash University, Clayton, VIC, Australia. suzie.miller@med.monash.edu.au
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Miller
authors.forename: Veena G
authors.initials: VG
authors.lastname: Supramaniam
authors.forename: Graham
authors.initials: G
authors.lastname: Jenkin
authors.forename: David W
authors.initials: DW
authors.lastname: Walker
authors.forename: Euan M
authors.initials: EM
authors.lastname: Wallace
mesh_terms: D000818:Animals; D001623:Betamethasone / Q000494:pharmacology* / Q000627:therapeutic use; D002319:Cardiovascular System / Q000187:drug effects*; D002560:Cerebrovascular Circulation; D003326:Coronary Circulation; D005260:Female; D005317:Fetal Growth Retardation / Q000188:drug therapy*; D005333:Fetus; D005938:Glucocorticoids / Q000494:pharmacology* / Q000627:therapeutic use; D010920:Placenta / Q000098:blood supply; D011247:Pregnancy; D012756:Sheep
chemical_list: D005938:Glucocorticoids; D001623:Betamethasone