In-vitro maturation (IVM) of oocytes retrieved from small follicles for steady response in stimulated in-vitro fertilization (IVF) cycles

Abstract

Objective: To evaluate the effectiveness of IVM for oocytes derived from steady-response IVF patients. Methods: Cohort study. Treatment results with IVM are described for those who had steady response after standard controlled ovarian stimulation for IVF. Oocytes were retrieved from small follicles in ovaries. Retrieved oocytes were assessed and cultured for further maturation. Maturation assessment were done at 0, 20, 25 hours after oocyte retrievals. Sperm insemination, embryo culture and day 2 embryo transfers were carried out as usual. Results including number of eggs, mature eggs, fertilization rate, embryo culture result and pregnancy rate after fresh transfers were recorded and presented. Results: From January 2012 to June 2013, there were 55 patients recruited. Mean female age was 30.5 ± 4.2 years. Mean AFC and AMH were 15.8 ± 6.0 and 8.7 ± 4.1, respectively. Mean oocytes retrieved and embryos transferred were 17.4 ± 10.7, and 3.3 ± 1.1, respectively. Transfer was cancelled in two cases due to unfavorable endometrium. Clinical pregnancy rate after fresh transfers was 32.1% (17/53) and implantation rate was 12.6%. Twenty-nine patients (54.7%) had extra embryos for cryopreservation after fresh transfers. Conclusion: IVM is feasible and effective for steady-response patients during ovarian stimulation in IVF treatment.