Prospective controlled study to evaluate laboratory and clinical outcomes of oocyte vitrification obtained in in vitro fertilization patients aged 30 to 39 years

ObjectiveTo determine whether the process of oocyte vitrification affects oocyte viability in in vitro fertilization (IVF) patients between 30 and 39 years of age.DesignProspective controlled study.SettingPrivate IVF practice.Patient(s)A total of 30 women assigned and 22 qualified.Intervention(s)Denudation of oocytes, cryopreservation of oocytes using vitrification method in a medium with 15% ethylene glycol (EG), 15% dimethylsulfoxide (DMSO), and 0.5 M sucrose.Main Outcome Measure(s)Oocyte survival, fertilization, day-3 embryo quality, blastocyst formation, clinical pregnancy, implantation, and live-birth rates.Result(s)After denudation of oocytes, mature sibling oocytes were randomly allocated to the fresh and vitrified groups. The survival rate was 79.6% after vitrification/warming. Overall, no statistically significant differences were found in fertilization, day-3 embryo quality, or blastocyst formation rates between the fresh and vitrified groups. The positive β-human chorionic gonadotropin, clinical pregnancy rate, and implantation rate were 13 (59.0%) of 22, 10 (45.4%) of 22, and 16 (30.1%) of 53 for the vitrified group. The overall efficiency in achieving a live birth was 11 (5.9%) of 186 per vitrified oocyte.Conclusion(s)The impact of vitrification can be reduced to a minimal level, making it possible to achieve high pregnancy and implantation rates in this age group of IVF patients.