#169 : The Use of PIEZO-ICSI Increases Fertilisation and Lowers Degeneration Rates when Compared to Conventional ICSI: In a Singapore Setting

Abstract

Background and Aims: PIEZO-ICSI was first introduced by Kimura & Yanagimachi in 1995 on mouse oocytes (1). It is a modified version of microinjection that uses piezoelectric pulses to enable fine movement of the needle. Further studies of PIEZO-ICSI on human oocytes showed improved outcomes in Japanese clinics (2-6) and similar findings were also reported by an Australian IVF group (7,8). In this study, we reflect on our experience using PIEZO-ICSI in a Singapore-based IVF clinic. Method: A retrospective study of 535 ICSI cycles was performed from January 2020 to December 2022, comprising of 157 cycles using Conventional ICSI and 378 cycles using PIEZO-ICSI. Primary outcomes were fertilisation, degeneration, blastulation and blastocyst usable rates. Secondary outcomes include clinical pregnancy, implantation and miscarriage rates. Patients who used donor gametes, surgically retrieved sperm or utilised cleavage-staged embryos were excluded. Two senior embryologists were responsible for the microinjections and had no prior experience with PIEZO-ICSI. Statistical significance for laboratory and clinical outcomes were determined using Mann-Whitney U Test and chi-square contingency tables, respectively. Results: The PIEZO-ICSI group showed significantly higher fertilisation (83.09% vs 69.62%, p<0.0001) and lower degeneration rates (3.17% vs 7.33%, p<0.0001) when compared to Conventional ICSI (Table 1). Blastulation (69.51% vs 64.86%, p=0.26) and blastocyst usable rates per 2PN (54.36% vs 51.26%, p=0.67) showed a higher trend in the PIEZO-ICSI group but did not meet statistical significance. The estimated time-to-competency for embryologists to achieve consistent outcomes with PIEZO-ICSI was three months (Figure 1). In terms of clinical outcomes, no significant differences were observed for clinical pregnancy (61.57% vs 56.97%, p=0.39), implantation (48.57% vs 43.59%, p=0.23) and miscarriage rates (23.70% vs 23.40%, p=0.96) between the PIEZO-ICSI and Conventional ICSI groups (Table 2). Conclusion: The use of PIEZO-ICSI improves fertilisation and degeneration outcomes when compared to Conventional ICSI in a Singapore-based IVF clinic.