title: Complete failure of fertilization in couples with unexplained infertility: implications for subsequent in vitro fertilization cycles.
abstract: OBJECTIVE
  To determine whether complete failure of fertilization of oocytes in couples with unexplained infertility persists during subsequent in vitro fertilization (IVF) cycles.
  
  
  METHODS
  A retrospective study of 120 cycles of IVF in 44 couples with unexplained infertility and complete failure of fertilization during their first IVF trial.
  
  
  METHODS
  In vitro fertilization unit of the Sheba Medical Center.
  
  
  METHODS
  Forty-four couples undergoing IVF for unexplained infertility.
  
  
  METHODS
  Fertilization rate of retrieved oocytes and pregnancy rate.
  
  
  RESULTS
  Of the initial 44 couples, 37 underwent additional IVF cycles and 30 (81.1%) achieved fertilization. Seven patients conceived during the study period as a result of IVF and two conceived spontaneously.
  
  
  CONCLUSIONS
  Complete failure of fertilization does not necessarily persist during subsequent IVF cycles. Therefore, at least two more IVF cycles should be attempted before reverting to other therapeutic options. However, although fertilization can be achieved in most couples, the mean oocyte fertilization rate during subsequent cycles in this group is low. This suggests an underlying undiagnosed pathology of oocyte/sperm interaction in some of these patients.
authors.affiliation: Department of Obstetrics and Gynecology, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Lipitz
authors.forename: J
authors.initials: J
authors.lastname: Rabinovici
authors.forename: I
authors.initials: I
authors.lastname: Ben-Shlomo
authors.forename: D
authors.initials: D
authors.lastname: Bider
authors.forename: Z
authors.initials: Z
authors.lastname: Ben-Rafael
authors.forename: S
authors.initials: S
authors.lastname: Mashiach
authors.forename: J
authors.initials: J
authors.lastname: Dor
mesh_terms: D005260:Female; D005307:Fertilization in Vitro; D005544:Forecasting; D006801:Humans; D007246:Infertility / Q000628:therapy*; D008297:Male; D012189:Retrospective Studies; D017211:Treatment Failure