title: Antenatal corticosteroid therapy: a comparative study of dexamethasone and betamethasone effects on fetal Doppler flow velocity waveforms.
abstract: OBJECTIVE
  To compare the effects of antenatal administration of dexamethasone and betamethasone, used in two different regimens, on fetal Doppler flow velocities.
  
  
  METHODS
  Sixty-seven women at risk for preterm delivery received course of corticosteroids by means of a computer-generated randomization table. The Doppler examination of the pulsatility index (PI) of the umbilical artery (UA), the middle cerebral artery (MCA) and the middle cerebral artery/umbilical artery PI ratio (MCA PI/UA PI) were performed before treatment, 24 and 72 h after the first dose of corticosteroids. The SAS system was used to perform statistical analysis.
  
  
  RESULTS
  No significant change was observed in UA PI through dexamethasone therapy. In MCA there was a significant decrease in PI at 72 h (2+/-0.43 before and 1.68+/-0.31 after, p=0.0001). Similarly a significant decrease in MCA PI/UA PI ratio was noted (2.09+/-0.51 before and 1.83+/-0.4 after, p=0.0137). No significant changes were observed in UA PI, MCA PI and MCA PI/UA PI ratio during betamethasone treatment.
  
  
  CONCLUSIONS
  Our results indicate significant decrease in fetal middle cerebral artery impedance at 72 h after maternal administration of the first dose of dexamethasone. Effects of dexamethasone on fetal brain warrants further research.
authors.affiliation: Department of Perinatology, Medical Academy of Bialystok, University Hospital, Sklodowska-Curie 24a, 15-276 Bialystok, Poland. urbanrem@amb.edu.pl
authors.forename: Remigiusz
authors.initials: R
authors.lastname: Urban
authors.forename: Adam
authors.initials: A
authors.lastname: Lemancewicz
authors.forename: Jerzy
authors.initials: J
authors.lastname: Przepieść
authors.forename: Jan
authors.initials: J
authors.lastname: Urban
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Kretowska
mesh_terms: D001623:Betamethasone / Q000008:administration & dosage*; D003907:Dexamethasone / Q000008:administration & dosage*; D005260:Female; D005865:Gestational Age; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D020768:Middle Cerebral Artery / Q000502:physiology; D007752:Obstetric Labor, Premature; D011247:Pregnancy; D011673:Pulsatile Flow; D012307:Risk Factors; D014469:Umbilical Arteries / Q000502:physiology
chemical_list: D005938:Glucocorticoids; D003907:Dexamethasone; D001623:Betamethasone