title: In-vitro maturation of germinal vesicle and metaphase I eggs prior to cryopreservation optimizes reproductive potential in patients undergoing fertility preservation.
abstract: OBJECTIVE
  To evaluate current and previous findings related to a timely implementation of in-vitro maturation (IVM) of germinal vesicle, metaphase I and metaphase II oocytes with an optimal cryopreservation to determine whether IVM should be attempted prior to (fresh IVM) or IVM after cryopreservation (postthaw IVM). Mitochondrion, chromatin and spindle formation in both groups were interpreted from referenced studies to establish best management of all oocytes.
  
  
  RESULTS
  The postthaw survival of germinal vesicle, metaphase I, fresh IVM-metaphase II and control metaphase II oocytes did not differ significantly [83.3% (n=9), 86.7% (n=12), 83% (n=57) and 86% (n=68), respectively]. Overall, combined survival and maturation were significantly higher (P<0.05) in the fresh IVM group at 63.8% (44 of 69) compared with the postthaw IVM group at 33.3% (nine of 27).
  
  
  CONCLUSIONS
  Conservation of retrieved immature oocytes after vaginal oocyte retrieval has become a major concern for patients, as they strive to maximize the reproductive viability of all oocytes obtained during treatment. Oocyte cryopreservation is important for patients at risk of ovarian cancer, elective fertility preservation and potentially for ovum donation. The superior maturation rate of germinal vesicle and metaphase I oocytes in the fresh IVM vs. postthaw groups provides strong impetus to mature oocytes to the metaphase II stage prior to cryopreservation.
authors.affiliation: aReproductive Medicine Associates of New York bDepartment of Obstetrics, Gynecology and Reproductive Science, Mount Sinai School of Medicine, New York, New York, USA.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Lee
authors.forename: Lucky
authors.initials: L
authors.lastname: Sekhon
authors.forename: Lawrence
authors.initials: L
authors.lastname: Grunfeld
authors.forename: Alan B
authors.initials: AB
authors.lastname: Copperman
mesh_terms: D002470:Cell Survival / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D005260:Female; D059247:Fertility Preservation / Q000379:methods*; D006801:Humans; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods; D008677:Metaphase / Q000502:physiology*; D054315:Oocyte Retrieval / Q000379:methods; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011247:Pregnancy; D027724:Reproductive Techniques, Assisted