title: The total pregnancy potential per oocyte aspiration after assisted reproduction-in how many cycles are biologically competent oocytes available?
abstract: OBJECTIVE
  While stimulation of women prior to assisted reproduction is associated with increased success rates, the total biological pregnancy potential per stimulation cycle is rarely assessed.
  
  
  METHODS
  Retrospective sequential cohort study of the cumulative live birth rate in 1148 first IVF/ICSI-cycles and 5-year follow up of frozen embryo replacement (FER) cycles were used. Oocyte number, number of embryos transferred, and cryopreserved/thawed and transferred embryos in a FER cycle were registered for all patients. Children per oocyte and per transferred embryo and percentage of cycles with births were calculated.
  
  
  RESULTS
  We obtained 9529 oocytes. Embryos (2507) were transferred in either fresh or FER cycles, resulting in 422 births and 474 live born children. Median age of the women was 32.5 years (range 20-41.5 years). In total, 34.3 % of all cycles ended with a live birth while in 65.7 % of the cycles, no oocytes were capable of developing into a child. The average number of oocytes needed per live born child after transfer of fresh and thawed embryos was 20 as only 5.0 % of oocytes aspirated in the first IVF/ICSI cycle had the competence to develop into a child.
  
  
  CONCLUSIONS
  In our setting, overall 5.0 % of the oocytes in a first cycle were biologically competent and in around 2/3 of all cycles, none of the oocytes had the potential to result in the birth of a child.
authors.affiliation: Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100-O, Copenhagen, Denmark.|Vitanova Fertility Center, Vester Voldgade 106 3rd floor, 1552-V, Copenhagen, Denmark.
authors.forename: J G
authors.initials: JG
authors.lastname: Lemmen
authors.affiliation: Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100-O, Copenhagen, Denmark.
authors.forename: N M
authors.initials: NM
authors.lastname: Rodríguez
authors.affiliation: Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100-O, Copenhagen, Denmark.
authors.forename: L D
authors.initials: LD
authors.lastname: Andreasen
authors.affiliation: Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100-O, Copenhagen, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Loft
authors.affiliation: Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100-O, Copenhagen, Denmark. soeren.ziebe@regionh.dk.
authors.forename: S
authors.initials: S
authors.lastname: Ziebe
mesh_terms: D000328:Adult; D001723:Birth Rate; D006063:Chorionic Gonadotropin / Q000097:blood; D015925:Cryopreservation; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D054315:Oocyte Retrieval / Q000379:methods*; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D006063:Chorionic Gonadotropin
keywords: Assisted reproduction; Competence; In vitro fertilization; Live birth; Oocytes; Utilization