title: Should metaphase 1 and 2 stages oocytes be vitrified in the same time for fertility preservation?
abstract: OBJECTIVE
  Could metaphase 1 (M1) and 2 (M2) stages oocytes from in vitro maturation (IVM) cycles and controlled-ovarian hyperstimulation (COH) cycles be frozen at the same time without any adverse effect of vitrification on further survival (SR) and maturation rates (MR)?
  
  
  METHODS
  M1 from cancer patients were prospectively included in IVM/COH groups, and in study or control subgroups if they were vitrified or not. In each study subgroup, SR were compared with that of M2 oocytes vitrified/warmed from egg donors. MR were compared with those of fresh-M1 oocytes from control IVM/COH subgroups.
  
  
  RESULTS
  SR were not different between groups. MR compared respectively between survived- and fresh-M1 oocytes were similar when resulting from COH (85.2 vs 81.1%) but significantly lower after IVM (39.1 vs 73.3%).
  
  
  CONCLUSIONS
  Simultaneous freezing of M1/M2 oocytes could be applied to COH but not to IVM during the course of fertility preservation.
authors.affiliation: Service d'Histologie-Embryologie-Cytogénétique-CECOS, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.|UFR de Santé, Médecine et Biologie Humaine, Université Paris 13, 93017 Bobigny Cedex, France.|Unité de Recherche en Epidémiologie Nutritionnelle, UMR U557 Inserm; U1125 Inra; Cnam; Université Paris 13, CRNH IdF, 93017 Bobigny, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Sifer
authors.affiliation: Service d'Histologie-Embryologie-Cytogénétique-CECOS, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.
authors.forename: Olivia
authors.initials: O
authors.lastname: Sellam-Chokron
authors.affiliation: Service d'Histologie-Embryologie-Cytogénétique-CECOS, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Sermondade
authors.affiliation: Service de Médecine de la Reproduction, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Cedrin-Durnerin
authors.affiliation: UFR de Santé, Médecine et Biologie Humaine, Université Paris 13, 93017 Bobigny Cedex, France.|Service de Médecine de la Reproduction, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Sonigo
authors.affiliation: Service d'Histologie-Embryologie-Cytogénétique-CECOS, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.|UFR de Santé, Médecine et Biologie Humaine, Université Paris 13, 93017 Bobigny Cedex, France.
authors.forename: Charlène
authors.initials: C
authors.lastname: Herbemont
authors.affiliation: UFR de Santé, Médecine et Biologie Humaine, Université Paris 13, 93017 Bobigny Cedex, France.|Service de Médecine de la Reproduction, Centre Hospitalier Universitaire Jean Verdier, Assistance Publique - Hôpitaux de Paris, 93143 Bondy, France.
authors.forename: Michael
authors.initials: M
authors.lastname: Grynberg
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002454:Cell Differentiation; D002478:Cells, Cultured; D015925:Cryopreservation / Q000379:methods; D005260:Female; D059247:Fertility Preservation; D006801:Humans; D066298:In Vitro Techniques; D008677:Metaphase; D009369:Neoplasms; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D010062:Ovulation Induction; D058989:Vitrification
keywords: controlled ovarian stimulation cycles; fertility preservation; in vitro maturation cycles; metaphase 1 stage oocyte; vitrification