Six years' experience in ovum donation using vitrified oocytes: report of cumulative outcomes, impact of storage time, and development of a predictive model for oocyte survival rate.
OBJECTIVE
To describe the clinical outcomes achieved after 6 years' experience in ovum donation conducted with vitrified oocytes; to attempt to find predictors of survival; and to provide information about the probability of having a baby according to the number of oocytes consumed.


METHODS
Retrospective, observational study.


METHODS
Private university-affiliated in vitro fertilization center.


METHODS
Recipients of vitrified oocytes (January 2007-March 2013), including all the warming procedures (n = 3,610) and all the donations made during the same period (n = 3,467).


METHODS
None.


METHODS
Survival rate per warming procedure, cumulative delivery rates (CDR) per single donation cycle, oocyte-to-baby rate, and cumulative live birth rate (CLBR) per oocyte consumed.


RESULTS
Oocyte survival rate was 90.4%. It was not possible to develop a predictive model for survival owing to the lack of prognostic value of the studied variables. Implantation, clinical, and ongoing pregnancy rates per donation cycle were 39.0% (95% confidence interval [CI], 37.8-40.5), 48.4% (95% CI, 46.7-50.1), and 39.9% (95% CI, 38.3-41.5), respectively. Statistical differences were found when comparing blastocysts versus day 3 ETs (42.5%; 95% CI, 40.4-45.2 vs. 37.5%; 95% CI, 35.3-39.7 ongoing pregnancy rate). The CDR/donation cycle, including cryotransfers, was 78.8% (95% CI, 73.5-84.1). The oocyte-to-baby rate was 6.5%. CLBR increased progressively according to the number of oocytes consumed.


CONCLUSIONS
We provide detailed information about the high efficiency of using vitrified/warmed oocytes. There is currently no way of estimating donors' oocytes survival when considering baseline characteristics, storage time, or controlled ovarian stimulation parameters. The probability of achieving a baby using vitrified oocytes increases progressively with the number of oocytes consumed.
IVI-Valencia, Institut Universitari IVI, Valencia, Spain. Electronic address: ana.cobo@ivi.es.
Ana
A
Cobo
IVI-Valencia, Institut Universitari IVI, Valencia, Spain.
Nicolás
N
Garrido
IVI-Valencia, Institut Universitari IVI, Valencia, Spain.
Antonio
A
Pellicer
IVI-Valencia, Institut Universitari IVI, Valencia, Spain.
José
J
Remohí
D000328:Adult; D018070:Biological Specimen Banks; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods*; D003661:Decision Support Techniques; D005260:Female; D005298:Fertility; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D050498:Live Birth; D018587:Oocyte Donation; D054315:Oocyte Retrieval; D009865:Oocytes / Q000473:pathology*; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013030:Spain; D013997:Time Factors; D016896:Treatment Outcome; D058989:Vitrification
Ovum donation; delivery rate; live birth; predictive value; survival rate; vitrification