title: Predictive value of the time interval between embryo loading and transfer for IVF/ICSI success: a prospective cohort study.
abstract: BACKGROUND
  The influence of embryo loading time (ELT) and the time interval between embryo loading and embryo transfer (TIEL-ET) on the success of IVF/ICSI is unknown.
  
  
  METHODS
  In a prospective cohort study, we aimed to ascertain the influence of ELT and TIEL-ET on ongoing pregnancy rate (OPR) and life birth rate (LBR). Data from 603 consecutive embryo transfers between January 2008 and December 2013 were collected. A complete data set including the outcomes of interest OPR and LBR was available for 410 women. The primary outcome was IVF/ICSI success, defined as OPR and LBR.
  
  
  RESULTS
  We used univariate and multivariate logistic regression for analysis. In a multivariate analysis, age (odds ratio [OR] 0.94; 95% confidence interval [CI] 0.89-0.99), catheter type (OR 0.45; 95% CI 0.24-0.84), and uterine length (OR 1.03; 95% CI 1.01-1.06), but not ELT and TIELT-ET were independently associated with OPR. Regarding LBR, age (OR 0.93; 95% CI 0.88-0.98), catheter type (OR 0.41; 95% CI 0.22-0.79), and uterine length (OR 1.03; 95% CI 1.01-1.06), but not ELT and TIELT-ET were independent predictors.
  
  
  CONCLUSIONS
  We conclude that speed of embryo transfer is not critical for the success of IVF/ICSI. However, care should be taken to choose catheter types proven to be associated with a high success rate.
authors.affiliation: Department of Obstetrics and Gynecology, Clinical Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. kazem.nouri@meduniwien.ac.at.
authors.forename: Kazem
authors.initials: K
authors.lastname: Nouri
authors.affiliation: Department of Obstetrics and Gynecology, Ruhr University Bochum, Bochum, Germany. clemens.tempfer@marienhospital-herne.de.|Marienhospital Herne, Hoelkeskampring 40, 44625, Herne, Germany. clemens.tempfer@marienhospital-herne.de.
authors.forename: Clemens B
authors.initials: CB
authors.lastname: Tempfer
authors.affiliation: Department of Obstetrics and Gynecology, Clinical Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. katharina.walch@meduniwien.ac.at.
authors.forename: Katharina
authors.initials: K
authors.lastname: Walch
authors.affiliation: Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. regina.promberger@meduniwien.ac.at.
authors.forename: Regina
authors.initials: R
authors.lastname: Promberger
authors.affiliation: Department of Obstetrics and Gynecology, Clinical Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. sema-dag@live.at.
authors.forename: Sema
authors.initials: S
authors.lastname: Dag
authors.affiliation: Department of Obstetrics and Gynecology, Clinical Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. johannes.ott@meduniwien.ac.at.
authors.forename: Johannes
authors.initials: J
authors.lastname: Ott
mesh_terms: D000328:Adult; D015331:Cohort Studies; D004624:Embryo Transfer / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D016015:Logistic Models; D015999:Multivariate Analysis; D011247:Pregnancy; D011256:Pregnancy Outcome; D018873:Pregnancy Rate; D020554:Sperm Injections, Intracytoplasmic; D013997:Time Factors