title: Embryo catheter loading and embryo culture techniques: results of a worldwide Web-based survey.
abstract: OBJECTIVE
  To identify trends in embryo catheter loading and embryo culture techniques performed worldwide.
  
  
  METHODS
  A retrospective evaluation using the results of a web-based survey, (IVF Worldwide ( www.IVF-worldwide.com ), was performed.
  
  
  RESULTS
  Responses from 265 centers in 71 countries were obtained. Most centers (97 %) preferred a catheter with its orifice on top, with only 3 % preferring a catheter with the orifice on its side; 41 % preferred a catheter marked for clear ultrasound view. The most commonly-reported methods of embryo loading were medium-air-embryo-air-medium (42 %), medium in catheter with embryo at end (20 %) and medium-air-embryo (15 %). In 68 % of centers the final volume of the catheter was up to 0.3 ml, with only 19 % using 0.3-0.5 ml and 1 % using 0.5-0.7 ml. Using reduced oxygen concentrations for embryo culture was divided between those who used it in combination with the two-gas system (34 %) and those who did not use it at all (39 %); 24 % reported using a three-gas system. Most clinics using reduced oxygen concentrations used it throughout the entire culture period. Half of centers (51 %) reported using reduced oxygen concentrations for the entire IVF population while 6 % reserved it only for blastocyst transfer. The use of sequential media was highly dominant with 40 % reporting its use.
authors.affiliation: Department of Gynecology and Obstetrics, Division of Reproductive Endocrinology, Johns Hopkins University School of Medicine, Baltimore, MD, USA, mchris21@jhmi.edu.
authors.forename: Mindy S
authors.initials: MS
authors.lastname: Christianson
authors.forename: Yulian
authors.initials: Y
authors.lastname: Zhao
authors.forename: Gon
authors.initials: G
authors.lastname: Shoham
authors.forename: Irit
authors.initials: I
authors.lastname: Granot
authors.forename: Anat
authors.initials: A
authors.lastname: Safran
authors.forename: Ayatallah
authors.initials: A
authors.lastname: Khafagy
authors.forename: Milton
authors.initials: M
authors.lastname: Leong
authors.forename: Zeev
authors.initials: Z
authors.lastname: Shoham
mesh_terms: D001755:Blastocyst; D002404:Catheterization / Q000295:instrumentation*; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D004624:Embryo Transfer / Q000295:instrumentation* / Q000379:methods; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007390:International Agencies; D020407:Internet; D012189:Retrospective Studies