Improvement of embryonic development and clinical outcomes of germinal vesicle stage oocytes using a microvibration culture system

Abstract

In vitro maturation (IVM) has evolved as a clinical treatment option in assisted reproductive technology. However, the poor developmental potential of germinal vesicle (GV)-stage oocytes is still suboptimal. This study's objective was to evaluate the effect of a microvibration culture system (MVC) during IVM and/or in vitro culture (IVC) on the clinical outcomes and the embryonic development potential of human GV-stage oocytes collected from human chorionic gonadotropin (HCG)-primed IVM and fertilization-embryo transfer (IVM/F-ET) cycles of patients with polycystic ovaries (PCO). A total of 206 HCG-primed IVM/F-ET cycles were divided into four groups according to the microvibration and static culture system applied during IVM and/or IVC: Group SS (static system during both IVM and IVC); Group SV (static system during IVM alternated with microvibration system during IVC); Group VS (microvibration system during IVM alternated with static system during IVC), and Group VV (microvibration system during both IVM and IVC). The results indicate that the rates of in vitro MII oocytes per cycle, fertilization, and cleavage were not significantly different between the groups. The rate of good-quality embryos in Group SV tended to be higher than the rate in Groups SS and VS, but there was no significant difference between Group SS and Group SV. Clinical pregnancy, implantation, and live birth rates of Groups SV and VS were slightly higher than those of Group SS. However, the rate of good-quality embryos with at least six cells on day 4, the clinical pregnancy, implantation, and live births in Group VV were significantly higher than those in Group SS. These results indicate that, compared with the static culture system, the MVC system applied for both IVM and IVC seems to improve the clinical outcomes and the quality of embryos of GV oocytes derived from HCG-primed IVM/F-ET cycles in PCO patients.Abbreviations: PCO: polycystic ovaries; HCG: human chorionic gonadotropin; GV: germinal vesicle; MII: metaphase II; IVM: in vitro maturation; IVF: in vitro fertilization; IVC: in vitro culture: MVC: microvibration culture; SC: static culture; ICSI: intracytoplasmic sperm injection; IVM/F-ET: IVM and fertilization-embryo transfer; AMH: anti-Mullerian hormone; OHSS: ovarian hyperstimulation syndrome