Oocyte Lysis following Intracytoplasmic Sperm Injection: Association with Measures of Oocyte Quality and Technician Performance

Abstract

The purpose of this investigation was to assess the incidence of oocyte damage (oocyte lysis) following intracytoplasmic sperm injection (ICSI) and its association with oocyte quality and with the personnel performing the procedure. Data concerning damage were accumulated from a laboratory database that tabulated the results of each patient's ICSI results. The incidence of lysis following ICSI was 4.8% of all injected oocytes. The number of oocytes injected and the incidence of intact (not lysed) oocytes that were fertilized by ICSI both were inversely correlated with the incidence of lysis. Individual technicians had distinctively different profiles of lysis, 1PN and 3PN embryos. Technicians in training had slightly elevated incidence of lysis. Whereas evidence is presented that both patient-specific oocyte quality and technician-specific performance are significantly related to the incidence of lysis, the small incremental incidence of lysis associated with each source leads us to believe that the incidence of lysis is largely unpredictable and unsystematic in nature.The author(s) have nothing to declare.

ALWAYS ICSI? A SWOT analysis

“…Technical factors are crucial for achieving high fertilization and pregnancy rates with ICSI and include the use of standardized ICSI pipettes, spermatozoon immobilization before injection, aspiration of a minimal amount of ooplasm before reinjection with the sperm, and substantial operator experience [39]. In a prospective trial involving 305 ICSI cycles, oocyte degeneration rate ranged from 5 to 11% depending on laboratory technician performance and the volume of aspirated oocyte cytoplasm during the procedure also affected the percentage of embryos reaching the blastocyst stage [40].…”

“…Selection of the oocytes ICSI allows a mechanical selection of the oocytes as patientspecific oocyte quality has been significantly related to the incidence of lysis during the procedure (evidence 2b) [39]. Moreover, the removal of the cumulus cells provides a more direct feedback on the oocyte maturity [59].…”

A novel device to micromanipulate oocytes during intracytoplasmic sperm injection

“…[2,3] One of the reasons attributed to the low success rate is the potential damage caused to the oolemma either during the oocyte immobilization process or during the sperm injection process. [4,5] Success of ICSI procedure depends on the skills of the operator as well as the quality of gametes. Specifically, when it comes to oocytes the quality depends on many factors including age and etiology of the patient.…”

“…Moreover, any prolonged mechanical trauma to the oocyte membrane during the micromanipulation process could result in rapid cell lysis. [4,6] The HP itself is susceptible to breakage during the ICSI process and there is limited control over pneumatic parameters such as suction pressure of the HP. We believe that a minimally invasive and non-pneumatic method to immobilize the oocyte would be relatively safer and more effective in ensuring the integrity of the oocyte during the ICSI process.…”