title: [Unselective single embryo transfer: chances of pregnancy related to operator experience].
abstract: BACKGROUND
  Selection of best quality embryo aims to achieve higher success rate, the pregnancy is unique and therefore obstetric risks are reduced.
  
  
  OBJECTIVE
  To evaluate the pregnancy rate with no transfer of selected single embryo (TSSE) three days versus the experience of the physician performing the embryo transfer.
  
  
  METHODS
  A retrospective, cross-sectional observational study in 159 patients Mexican Fertility Center in CEPAM protocol in vitro fertilization any indication, other ovulatory disorders and who was only possible obtain an embryo to be transferred in three day. For the analysis were grouped according to age, number of cells of the embryo transfer day and the doctor performed. Continuous variables are reported as means and standard deviations and univariate logistic regression was performed to determine statistical significance. Categorical variables were evaluated in frequencies and percentages. The calculations were performed with the software JMP.
  
  
  RESULTS
  Protocol of single-embryo transfer not selected in three day pregnancy rate of 17% was obtained, with lower rates in women over 40 years of age and older embryos of more than 9 cells but also higher rate abortion. More experienced doctors achieved better pregnancy rates.
  
  
  CONCLUSIONS
  This is the first study in Mexican population to assess the possibility of pregnancy with single embryo transfer in selected post-harvest with a three day success rate of 17% and first-order variables: number of cells on the day of transfer and experience of the physician who performed the procedure.
authors.forename: Alberto
authors.initials: A
authors.lastname: Kably-Ambe
authors.forename: Esperanza
authors.initials: E
authors.lastname: Carballo-Mondragón
authors.forename: Armando Miguel
authors.initials: AM
authors.lastname: Roque-Sánchez
authors.forename: Leonor
authors.initials: L
authors.lastname: Durán-Monterrosas
authors.forename: Jorge
authors.initials: J
authors.lastname: Campos-Cañas
mesh_terms: D000328:Adult; D002983:Clinical Competence; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D056826:Single Embryo Transfer / Q000592:standards