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.

A Comparison of Embryonic Development and Clinical Outcomes between In vitro Oocytes Maturation Using Micro-Vibration System and In vivo Oocytes Maturation in Polycystic Ovarian Syndrome Patients

“…Furthermore, Hur et al [9] found that rates of blastocyst development on day 5, pregnancy, and implantation were increased with the MVC system compared with the SC system in poor responder patients. Positive effects of mechanical micro-vibration have been shown in our previous study of IVM cycles [13]. The same previous study indicated that the MVC system applied during both IVM and IVC was able to produce higher rates of GQE and clinical pregnancy compared with the SC system [13].…”

“…Positive effects of mechanical micro-vibration have been shown in our previous study of IVM cycles [13]. The same previous study indicated that the MVC system applied during both IVM and IVC was able to produce higher rates of GQE and clinical pregnancy compared with the SC system [13]. The results of the present study *, ** Significant difference between the IVM-S and IVM-MV groups (* p = 0.045, ** p = 0.041).…”

“…The IVM cycles procedures (IVM-S or IVM-MV groups) were performed as described previously [13]. When the endometrial thickness reached at least 6 mm, human chorionic gonadotropin (hCG; 10,000 IU; IVF-C; LG, Seoul, Korea) was administered, and ovum pick-up was performed 36 h later under ultrasound guidance using a 19-gauge aspiration needle (COOK, Eight Mile Plains, Queensland, Australia) with a pressure of 80-100 mm Hg.…”

“…The MVC system of the IVM-MV group was added with a micro-vibrator (NSSB-300N; NepaGene, Ichikawa, Japan) under the same procedure, media, and incubator conditions as those mentioned above for SC system. The micro-vibrator was set at a frequency of 26.3 Hz for every 5 s at 1-h intervals for IVM and at a frequency of 41.2 Hz for every 5 s at 1-h intervals for IVC based on a previous study [13].…”

“…Additionally, a study using micro-vibration on the immature oocytes of pigs showed that mechanical vibration can increase the cytoplasmic maturation of in vitro-matured oocytes in pigs, resulting in improved blastocyst development [12]. A previous, prospective study has demonstrated that the MVC system tends to enhance the clinical outcomes and quality of embryos of germinal vesicle (GV) oocytes derived from the IVM treatment cycle in PCO patients compared with the SC system [13]. However, it remains unknown whether the embryo development potential of GV oocytes utilizing the MVC system is as capable as that of in vivo-matured oocytes for embryogenesis.…”