Improved fertilization, degeneration, and embryo quality rates with PIEZO-intracytoplasmic sperm injection compared with conventional intracytoplasmic sperm injection: a sibling oocyte split multicenter trial

Abstract

Objective: To investigate whether PIEZO-intracytoplasmic sperm injection (PIEZO-ICSI) increases the fertilization rate, decreases the degeneration rate, and increases the utilization rate per oocyte injected compared with conventional intracytoplasmic sperm injection (ICSI).

Design: Sibling oocyte split multicenter trial.

Setting: Fertility clinics.

Patients: Women with a diagnosis of infertility who used ICSI as their method of insemination and had ≥6 mature oocytes for injection.

Interventions: Participants had their mature oocyte cohort divided, where half were injected using conventional ICSI and the other half were injected using PIEZO-ICSI. For patients with an uneven oocyte number, the extra oocyte was injected using conventional ICSI. The injection technique used first was also randomized to ensure that there was no bias due to order of injection.

Main outcome measure: The primary outcome measure was the fertilization rate after injection.

Results: A total of 108 patients underwent a sibling split use of conventional ICSI and PIEZO-ICSI. The fertilization rate was 71.6% in PIEZO-ICSI, which significantly increased compared with that in conventional ICSI 65.6%. In addition, the oocyte degeneration rate decreased in PIEZO-ICSI compared with that in conventional ICSI (6.3% vs. 12.1% respectively), and the blastocyst quality increased, as measured by the number of grade A and B quality blastocysts present on day 5 of development (33.3% vs. 27.5%). No significant differences in the aneuploidy or utilization rate, clinical pregnancy, or live birth outcome after single embryo transfer were noted between the two injection techniques.

Conclusions: This trial supports the possibility that PIEZO-ICSI increases the fertilization rates, decreases the oocyte degeneration rates, and increases the blastocyst quality compared with conventional ICSI; however, it does not appear to influence the clinical pregnancy or live birth rate per transfer.

Clinician trial registration number: Australian and New Zealand Clinical Trial Registry ACTRN12620000407998.

Keywords: ICSI; PIEZO; degeneration; embryo quality; fertilization.