Live birth after vitrification of in vitro matured human oocytes

ObjectiveTo report the first healthy live birth from immature oocytes retrieved in a natural menstrual cycle, followed by in vitro maturation (IVM) and cryopreservation of the oocytes by vitrification.DesignCase report.SettingUniversity-based tertiary medical center.Patient(s)A 27-year-old woman with tubal disease and polycystic ovaries.Intervention(s)Immature oocytes were retrieved by transvaginal ultrasound guided follicle aspiration on day 13 of her natural menstrual cycle, matured in vitro and vitrified. The oocytes were thawed in a subsequent menstrual cycle, inseminated by intracytoplasmic sperm injection, and the resulting embryos transferred.Main Outcome Measure(s)Oocyte maturation and survival rates, pregnancy, and live birth.Result(s)One metaphase II and 18 germinal vesicle stage oocytes were collected; 16 out of 18 germinal vesicle oocytes matured, and a total of 17 oocytes were vitrified. After thawing, four IVM oocytes survived; three embryos were transferred. The woman went on to deliver a single healthy live baby at term.Conclusion(s)We provide proof-of-principle evidence that the novel fertility preservation strategy of immature oocyte retrieval, IVM, and vitrification of oocytes can lead to successful pregnancy and healthy live birth.