title: Air in the transfer catheter does not affect the success of embryo transfer.
abstract: OBJECTIVE
  To investigate the effect on embryo transfer (ET) success of air loaded into the transfer catheter to bracket the embryo-containing medium.
  
  
  METHODS
  Prospective, randomized study.
  
  
  METHODS
  University teaching hospital.
  
  
  METHODS
  One hundred two consecutive patients undergoing ET after IVF.
  
  
  METHODS
  In group 1 (n = 52), embryos were loaded as follows: 200 microL of air in the syringe, 100-125 microL of air in the proximal part of the catheter, 20-25 microL of medium containing the embryos to be transferred, and 10 microL of air at the tip of the catheter. In group 2 (n = 50), the syringe and the entire catheter were filled with medium and the embryo-containing medium (20-25 microL) was aspirated without being bracketed by air spaces.
  
  
  METHODS
  Implantation and pregnancy rates.
  
  
  RESULTS
  No differences were found between groups 1 and 2 with respect to implantation and pregnancy rates.
  
  
  CONCLUSIONS
  The air loaded into the transfer catheter to bracket the embryo-containing medium has no negative effect on ET success.
authors.affiliation: Institut Clínic of Gynecology and Obstetrics, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi i Sunyer, Faculty of Medicine-University of Barcelona, Barcelona, Spain.
authors.forename: Vicenta
authors.initials: V
authors.lastname: Moreno
authors.forename: Juan
authors.initials: J
authors.lastname: Balasch
authors.forename: Ester
authors.initials: E
authors.lastname: Vidal
authors.forename: Josep M
authors.initials: JM
authors.lastname: Calafell
authors.forename: Salvadora
authors.initials: S
authors.lastname: Cívico
authors.forename: Juan A
authors.initials: JA
authors.lastname: Vanrell
mesh_terms: D000388:Air; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008297:Male; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic