title: Betamethasone associated changes in umbilical artery flow velocity waveforms in multiple pregnancies with umbilical artery absent end diastolic flow.
abstract: OBJECTIVE
  It has been previously shown that glucocorticoids alter umbilical artery flow velocity waveforms in singleton pregnancies complicated by umbilical artery absent end diastolic flow. Whether similar effects are evident in multiple pregnancies where one fetus has umbilical artery absent end diastolic flow is not known.
  
  
  METHODS
  Women with a twin or triplet pregnancy complicated by umbilical artery absent end diastolic flow in one fetus were admitted to hospital for intensive fetal surveillance including daily umbilical artery flow velocity waveform studies, as per hospital protocol. All women received prophylactic betamethasone (11.4 mg x 2, 24 h apart) in anticipation of preterm delivery.
  
  
  RESULTS
  Between October 1996 and February 2002, 24 women with a multiple pregnancy complicated by umbilical artery absent end diastolic flow were cared for. Of these, six had a pregnancy with feto-fetal transfusion and excluded from further analysis. Of the remaining 18 women, eight had monochorionic diamniotic twins, eight had dichorionic twins, and two had trichorionic, triamniotic triplets. The median (range) gestation at diagnosis of umbilical artery absent end diastolic flow was 210.5 days (173-241). In nine (50%) of the 18 pregnancies the administration of betamethasone was associated with return of umbilical artery end diastolic flow for a median of 5 days. There was no association between this effect and chorionicity. The median (range) interval from diagnosis of umbilical artery absent end diastolic flow to delivery was 11 days (1-46).
  
  
  CONCLUSIONS
  As previously reported in singleton pregnancies, the maternal administration of betamethasone in multiple pregnancies with umbilical artery absent end diastolic flow is associated with a transient return of end diastolic flow.
authors.affiliation: Maternal-Fetal Medicine Unit, Monash Medical Centre, Southern Health, Clayton, Victoria, Australia. a.barkehallthomas@southernhealth.org.au
authors.forename: Andrea
authors.initials: A
authors.lastname: Barkehall-Thomas
authors.forename: Melanie
authors.initials: M
authors.lastname: Thompson
authors.forename: Lesleigh S
authors.initials: LS
authors.lastname: Baker
authors.forename: Andrew
authors.initials: A
authors.lastname: Edwards
authors.forename: Euan M
authors.initials: EM
authors.lastname: Wallace
mesh_terms: D001623:Betamethasone / Q000494:pharmacology*; D001783:Blood Flow Velocity / Q000187:drug effects* / Q000502:physiology; D003971:Diastole / Q000502:physiology; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000187:drug effects / Q000502:physiology*; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D014310:Triplets; D014427:Twins; D016216:Ultrasonography, Prenatal / Q000187:drug effects*; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology*
chemical_list: D005938:Glucocorticoids; D001623:Betamethasone