Artificial oocyte activation improves ICSI outcomes following unexplained fertilization abnormalities

Area of Science:

• Reproductive Medicine
• Assisted Reproductive Technology
• Infertility Research

Background:

• Unexplained low or no fertilization after in vitro fertilization/intracytoplascial sperm injection (IVF/ICSI) poses a significant challenge in assisted reproduction.
• Identifying the underlying causes, such as phospholipase C zeta (PLCζ) deficiency, is crucial for effective treatment.

Purpose of the Study:

• To evaluate the efficacy of artificial oocyte activation (AOA) in improving fertilization and pregnancy outcomes for patients with unexplained fertilization failure following IVF/ICSI.
• To assess the diagnostic value of PLCζ protein expression assays in patient selection for ICSI-AOA.

Main Methods:

• A retrospective case-control cohort study reviewed 231 IVF/ICSI cases with fertilization failure or rates ≤25% between 2014-2021.
• Patients with unexplained abnormalities underwent investigations, including sperm immunocytochemistry for PLCζ. Thirty-nine couples subsequently underwent ICSI with AOA using a calcium ionophore.

Main Results:

• ICSI-AOA significantly improved fertilization rates (57.2% vs. 7.1%, P < 0.0001) compared to preceding IVF/ICSI.
• For patients with PLCζ deficiency, ICSI-AOA yielded a fertilization rate of 66.3% (vs. 4.6%, P < 0.0001).
• ICSI-AOA led to higher rates of embryo transfer, clinical pregnancy, live birth, and cryopreservation of surplus embryos.

Conclusions:

• Artificial oocyte activation (AOA) is a highly effective intervention for couples with unexplained fertilization abnormalities, transforming clinical outcomes.
• PLCζ assays can serve as valuable diagnostic tools for selecting patients who would benefit most from ICSI-AOA.
• Continued research and development of PLCζ assays are recommended to optimize patient selection for ICSI-AOA.