title: Evidence of early placental vascular anastomosis during selective embryo reduction in monozygotic twins.
abstract: OBJECTIVE
  To describe selective embryo reduction of two triplet pregnancies with a monozygotic twin.
  
  
  METHODS
  Case reports.
  
  
  METHODS
  Infertility unit of a Department of Obstetrics and Gynecology.
  
  
  METHODS
  Two patients treated with IVF-ET who had triplet pregnancies.
  
  
  METHODS
  Selective embryo reduction of monozygotic twins.
  
  
  METHODS
  Fetal heart beat.
  
  
  RESULTS
  During intracardiac injection of potassium chloride plus midazolam in one of the monozygotic twin fetuses, we observed an immediate diminution of the cardiac pulse rate of the second twin. This phenomenon was observed in both patients.
  
  
  CONCLUSIONS
  These observations clearly indicate the presence of vascular anastomosis between the two fetuses of these monozygotic twins. Thus, use of toxic substance to reduce one of the two fetuses of a monozygotic twin pregnancy is contraindicated. In cases of triplets that include a monozygotic twin, it is safest to interrupt the evolution of the twin if selective reduction is desired.
authors.affiliation: Service de Gynécologie-Obstétrique, Hôpital Antoine Béclère, Clamart, France.
authors.forename: François
authors.initials: F
authors.lastname: Olivennes
authors.forename: Severin
authors.initials: S
authors.lastname: Doumerc
authors.forename: Marie Victoire
authors.initials: MV
authors.lastname: Senat
authors.forename: François
authors.initials: F
authors.lastname: Audibert
authors.forename: Renato
authors.initials: R
authors.lastname: Fanchin
authors.forename: René
authors.initials: R
authors.lastname: Frydman
mesh_terms: D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006340:Heart Rate, Fetal / Q000502:physiology; D006801:Humans; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000517:prevention & control; D018607:Pregnancy Reduction, Multifetal / Q000379:methods*; D014310:Triplets; D014430:Twins, Monozygotic