title: High cumulative live births in oocyte donation cycles with cryopreservation of all embryos.
abstract: BACKGROUND
  Cryopreservation of all embryos in stimulated IVF cycles is occasionally necessary. Although it is known that frozen embryo transfer results in lower live birth rates per transfer, there is limited information regarding expected cumulative live birth rates for patients who are in this particular scenario.
  
  
  METHODS
  The objective was to evaluate long-term outcomes in cycles undergoing pronuclear cryopreservation of all embryos utilizing a retrospective analysis of 154 consecutive recipients from 1995 to 2006.
  
  
  RESULTS
  The cumulative rate of first live birth per retrieval was 66.2%, with a 36.4% live birth rate per frozen embryo transfer. Following an average 2.2 +/- 0.98 transfers, 32.6% (17/52) of patients who never delivered had remaining embryos making the cumulative first live birth rate previously stated a conservative estimate. 11.7% of recipients had sibling deliveries from a single retrieval. Over 1/3 of the delivered recipients have remaining cryopreserved embryos and could pursue an additional pregnancy.
  
  
  CONCLUSIONS
  These results suggest that pronuclear cryopreservation of all embryos in an oocyte donation cycle maintains good cumulative live birth rates, as well as chances for a sibling from a single retrieval. Recipients who must delay transfer can be reassured a high potential for live birth from their first donor retrieval.
authors.affiliation: Department of Obstetrics and Gynecology, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Tatpati
authors.forename: Susan B
authors.initials: SB
authors.lastname: Hudson
authors.forename: Puja S
authors.initials: PS
authors.lastname: Gera
authors.forename: Michael C
authors.initials: MC
authors.lastname: Allemand
authors.forename: Sherry
authors.initials: S
authors.lastname: Stevens-Hall
authors.forename: Mark A
authors.initials: MA
authors.lastname: Wentworth
authors.forename: Charles C
authors.initials: CC
authors.lastname: Coddington
mesh_terms: D000328:Adult; D015925:Cryopreservation / Q000706:statistics & numerical data*; D004624:Embryo Transfer / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D018587:Oocyte Donation / Q000706:statistics & numerical data*; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D018873:Pregnancy Rate; D012189:Retrospective Studies