Identifying optimal puncture position by a real-time image analysis for Piezo-ICSI: a prospective randomized sibling oocyte study

Abstract

Research question: Would the use of the intracytoplasmic sperm injection (ICSI) position detector (IPD) make it possible to identify the optimal puncture position on oolemma during Piezo-ICSI and reduce oocyte degeneration and unintentional membrane rupture (UMR)?

Design: This sibling oocyte study included 917 inseminated oocytes from 113 infertile patients undergoing Piezo-ICSI. Oocytes were randomly divided into two groups: with or without IPD. The rates of UMR, degeneration, fertilization and embryonic development were compared between the two groups. As a secondary analysis, non-IPD oocytes were retrospectively assessed as appropriate or non-appropriate injection sites and analysed alongside prospective 'appropriate' injections.

Results: The rates of UMR (7.0% versus 12.9%, P = 0.004) and degeneration (2.4% versus 6.1%, P < 0.01 = 0.008) were significantly lower in the IPD group than in the non-IPD group. No significant differences, however, were observed in the rates of fertilization (two pronuclei, 83.8% versus 78.9%), blastocyst formation (48.5% versus 48.8%) or good-quality blastocysts (22.5% versus 20.5%). Additionally, no significant differences were observed in the rates of pregnancy (29.4% versus 35.1%) or live births (26.5% versus 29.7%) in a single embryo transfer setting with or without IPD. Comparing all 'appropriate' injections with 'non-appropriate' injections also showed a significantly decreased rate of UMR and degeneration (both P ≤ 0.001).

Conclusions: The present study demonstrated that a real-time image analysis during Piezo-ICSI markedly reduced oocyte degeneration by avoiding areas associated with a high risk of UMR. Therefore, IPD may increase the number of embryos available for treatment.

Keywords: ICSI; Image analysis; Oocyte degeneration; Piezo-ICSI; Unintentional membrane rupture.