Intracytoplasmic Sperm Injection Techniques in Non-Male Factor Infertility

The advent of intracytoplasmic sperm injection (ICSI) revolutionised assisted reproductive technology by enabling direct microinjection of a single sperm into the oocyte cytoplasm. Although originally conceived for male factor infertility, ICSI has been widely adopted in cases of non-male factor infertility—encompassing female-only or unexplained subfertility. Contemporary research has scrutinised whether this invasive technique confers advantages over conventional in vitro insemination in populations where sperm parameters fall within normal limits. Studies have compared key performance indicators such as fertilisation rates, embryo cleavage and blastocyst formation, implantation success and live birth outcomes. While ICSI consistently yields higher fertilisation and lower cycle cancellation rates, evidence on implantation and live birth suggests no clear overall benefit—particularly in female-only and unexplained infertility. Select subgroups, including patients with prior poor-quality embryos or specific immunological profiles, may experience improved embryo morphology and clinical pregnancy rates under ICSI protocols. The balance of laboratory efficiency, clinical effectiveness, cost, and potential impact on offspring safety underlines the need for judicious application of ICSI beyond male factor indications.

Research from Nature Portfolio

A recent large-scale retrospective cohort compared conventional insemination and ICSI in women with autoimmune thyroid conditions and non-male factor infertility. Propensity score matching ensured comparable baseline characteristics. Results demonstrated that ICSI did not improve fertilisation success or the development of high-quality cleavage embryos and was associated with lower usable blastocyst rates. Although clinical pregnancy and live birth rates did not differ significantly, the study concluded that ICSI neither enhances embryo development potential nor increases live birth outcomes in this population, emphasising the importance of randomised trials to guide practice.

Intracytoplasmic Sperm Injection Techniques in Non-Male Factor Infertility publication trend

The graph below shows the total number of articles in intracytoplasmic sperm injection techniques in non-male factor infertility across all publications each year (not limited to Nature Index journals).

Technical terms

Intracytoplasmic Sperm Injection (ICSI): A micromanipulation technique in which a single sperm is injected directly into the oocyte cytoplasm.

Non-male factor infertility: Infertility cases where sperm parameters are normal and reproductive impediments arise from female or unexplained causes.

Fertilisation rate: The percentage of oocytes that undergo successful union with sperm and form pronuclei.

Blastocyst: A stage-5 preimplantation embryo characterised by an inner cell mass and a fluid-filled cavity.

Live birth rate: The proportion of initiated treatment cycles resulting in a live neonate.

Embryo quality: A composite metric assessing morphology, cleavage speed and developmental competence.

References

1. Comparisons of conventional in vitro fertilization versus intracytoplasmic sperm injection in women with thyroid autoimmunity and non-male factor infertility, a propensity score matching analysis. Scientific Reports (2023).
2. Intracytoplasmic sperm injection versus conventional in vitro insemination in couples with non-male infertility factor in the ‘real-world’ setting: analysis of the HFEA registry. Journal of Translational Medicine (2024).
3. Impact of intracytoplasmic sperm injection in women with non-male factor infertility: A systematic review and meta-analysis. Frontiers in Reproductive Health (2022).
4. Should ICSI be implemented on patients with poor-quality embryos in the previous IVF cycle?. Heliyon (2023).