P-127 Identification of the optimal puncture position by image analysis may reduce oocyte degeneration in intracytoplasmic sperm injection (ICSI)
Authors: Morimoto T , Maekawa T , Mizuta S , Matsubayashi H , Takeuchi T , Hata Y , Ishikawa T 
Published: June 2022

Abstract

Study question
Is it possible to identify the optimal puncture position by image analysis where oocyte degeneration is reduced in ICSI procedure?

Summary answer
Visualizing the likelihood of unintentional membrane rupture (UMR) using image analysis can reduce oocyte degeneration and thereby generate more embryos available for treatment.

What is known already
It is known that the oocyte degeneration after both conventional-ICSI and Piezo-ICSI are often observed when UMR occurs during the puncturing process and the likelihood of UMR may depends on the location of the puncture site on the oolemma. Identifying the appropriate puncturing position may decrease the likelihood of membrane rupture and thus degeneration, however, there are no studies identifying the optimal puncture position during ICSI.

Study design, size, duration
We have developed the ICSI Position Detector (IPD), which can identify an area where rupture is likely to occur and visualize it on a video monitor. This study included 1,110 mature oocytes retrieved from 190 consenting patients. Matured oocytes were inseminated either by Conventional-ICSI (n = 437, average maternal age: 39.1±4.6 y.o.) or Piezo-ICSI (n = 673, average maternal age: 38.6±4.5 y.o.). ICSI was performed blindly, moving images were recorded and analyzed retrospectively during ICSI using IPD.

Participants/materials, setting, methods
Inseminated oocytes were subsequently divided into two groups according to IPD results, oocytes on which ICSI was performed at the position with a low chance of UMR (appropriate group), and with a high chance of UMR (non-appropriate group) by IPD. The rates of UMR, degeneration, fertilization (2PN), blastocyst formation, and good-quality blastocyst (Grade 3BB and above on day 5 by the Gardner scoring) were compared between the two groups of both conventional-ICSI and Piezo-ICSI.

Main results and the role of chance
The areas in which UMR is less likely to occur and more likely to occur are heterogeneously distributed. When ICSI was performed blindly, about half was from the non-appropriate position. In appropriate group of Piezo-ICSI, rates of UMR (4.3% vs. 17.4%, P &lt; 0.001) and degeneration (1.0% vs. 5.7%, P &lt; 0.001) were significantly lower than those of non-appropriate group, whereas rates of fertilization (88.0% vs. 78.4%, P &lt; 0.01) and blastocyst formation (57.8% vs. 45.9%, P &lt; 0.01) were significantly higher than those of non-appropriate group, respectively. The rate of good-quality blastocyst (28.8% vs. 24.9%) was in favor of appropriate group, but not significantly different. In appropriate group of Conventional-ICSI, rates of UMR (6.7% vs. 20.6%, P &lt; 0.001) and degeneration (1.5% vs. 6.6%, P &lt; 0.01) were significantly lower than those of non-appropriate group, whereas rate of fertilization (88.7% vs. 69.5, P &lt; 0.001) was significantly higher than those of non-appropriate group, respectively. The rates of blastocyst formation (37.5% vs. 35.3%), good-quality blastocyst (21.3% vs. 18.7%) were all in favor of appropriate group, but not significantly different.

Limitations, reasons for caution
This is a single private fertility clinic study. Its reproducibility should be assessed in different laboratory conditions and the hands of different operators. Moreover, specific studies should be addressed on the effect of the other putative confounders under investigation (e.g. kind of ovulation trigger, patient demographics, culture environment, etc.).

Wider implications of the findings
This study demonstrated that the IPD is useful to identify the optimal puncture location site to prevent UMR on ICSI procedure, resulting in reducing UMR and degeneration of the oocytes and increasing culture results, thereby, generating more embryos available for transfer or cryopreservation.

Trial registration number
not applicable