title: Normal pregnancy resulting from a non-pronuclear oocyte at the time of examination for fertilization.
abstract: OBJECTIVE
  To report the case of a patient undergoing in vitro fertilization (IVF) in which a non-pronuclear (0PN) oocyte resulted in a normal pregnancy.
  
  
  METHODS
  A 36-year-old woman underwent an IVF-embryo transfer treatment cycle.
  
  
  RESULTS
  Four oocytes were retrieved for insemination by IVF. Examination for fertilization revealed two polypronuclearpolygynic and two non-pronuclear oocytes. The non-pronuclear oocytes were observed further for development. One embryo developed from the non-pronuclear cohort and was transferred at the 8-cell stage on day 3. Subsequently, a pregnancy developed, and resulted in the delivery of a healthy term infant.
  
  
  CONCLUSIONS
  Non-pronuclear oocytes may represent a source of developmentally competent embryos, and further observation of this cohort should be considered, particularly in situations involving a low yield of oocytes at retrieval.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA 94305-5317, USA.
authors.forename: R O
authors.initials: RO
authors.lastname: Burney
authors.forename: J
authors.initials: J
authors.lastname: Gebhardt
authors.forename: Y
authors.initials: Y
authors.lastname: Shu
authors.forename: B
authors.initials: B
authors.lastname: Behr
authors.forename: L M
authors.initials: LM
authors.lastname: Westphal