Work

Protocol for assisted sperm fusion insemination of human oocytes using zona pellucida-bound sperm

Year: 2026

Type: article

Abstract: Oocyte degeneration is a critical and persistent limitation of intracytoplasmic sperm injection (ICSI). Here, we present assisted sperm fusion insemination (ASFI), a protocol for fertilizing human oocytes using zona pellucida-bound sperm (ZP-sperm) to minimize oocyte degeneration while preserving cellular integrity. We describe steps for co-culturing immature or degenerated oocytes with sperm, harvesting ZP-sperm, and facilitating their attachment to and fusion with oocytes. This protocol uses standard ICSI equipment and provides a reproducible approach for minimizing the mechanical stress during fertilization. For complete details on the use and execution of this protocol, please refer to Hatakeyama et al. 1 1. Hatakeyama, S. ∙ Koizumi, K. ∙ Kuramoto, G. ... Assisted sperm fusion insemination improves fertilization rates and increases usable embryos for transfer: a clinical sibling-oocyte study F. S. Rep. 2025; 6 :17-24 Full Text Full Text (PDF) Scopus (6) PubMed Google Scholar

Source: STAR Protocols

DOI: 10.1016/j.xpro.2026.104781

Authors: Shota Hatakeyama, Koji Nakagawa, Shirei Ohgi, Rikikazu Sugiyama

Institutions: Center for Reproductive Medicine and Implantation Research, Sugiyama Clinic, Sugiyama Clinic Marunouchi

Language: English

Topic: Reproductive Biology and Fertility

Subfield: Reproductive Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,550