Antisperm Antibodies and Autoimmunity in the Era of Assisted Reproduction

Antisperm antibodies affect 5–12% of infertile men; immunosuppression was abandoned as ineffective — ICSI now mechanically bypasses the immune barrier at >80% antibody binding

Journal: Fertility and Sterility | Published: 2026-03-09 | Type: Narrative Review | PMID: 41812699 Authors: Mass Lindenbaum M, Kuribayashi S, Lundy SD (Glickman Urological Institute, Cleveland Clinic Foundation, Cleveland, Ohio) Funding/COI: Funding not listed. Lundy reports NIH funding and Velosano support outside this work; serves on PS Fertility Advisory Board and as Legacy Health Consultant. Other authors: no disclosures.

Summary

Antisperm antibodies (ASA) arise when the blood-testis barrier fails — through trauma, obstruction, or inflammation — exposing sperm antigens to the immune system. The resulting IgG and IgA antibodies impair motility, block cervical mucus penetration, and interfere with fertilization. This review traces the field's evolution from routine ASA screening and systemic immunosuppression (now abandoned as ineffective and harmful) to a targeted triage approach where the antibody burden level dictates whether IUI or ICSI is warranted.

Claims

• Male factor infertility contributes to approximately 50% of all infertility cases
• ASA affects 5–12% of infertile men
• Primary diagnostic tools: mixed antiglobulin reaction (MAR) and immunobead test — direct assays that detect surface-bound antibodies
• Contemporary guidelines discourage universal ASA screening; testing is now reserved for "gray zone" cases — unexplained infertility or isolated asthenozoospermia — where results alter management
• At lower antibody-binding levels, IUI remains viable
• At >80% sperm autoimmunization, IUI is ineffective; ICSI is required to mechanically bypass the immune barrier
• Systemic immunosuppression (historically corticosteroids) has been largely abandoned due to poor efficacy and significant adverse effects

Study Quality

This is a narrative review, not a systematic review or meta-analysis, so it carries the inherent limitations of the format: no explicit search strategy, no quality assessment of included studies, and no pooled effect sizes. The "management-oriented algorithm" it proposes is based on expert synthesis, not a formal evidence-grading process. The authors acknowledge the shift in clinical practice away from immunosuppression without quantifying how many studies support that shift or what their quality was.

That said, for a review article covering a niche immunological corner of male infertility, the scope is appropriate. It addresses pathophysiology, diagnostics, and clinical decision-making in a structured way. The Cleveland Clinic affiliation lends institutional credibility, but that's not a substitute for methodological rigor.

Red Flags

• Narrative review format — no systematic search, no PRISMA, no risk-of-bias assessment
• Funding source not disclosed for this specific paper — Lundy's external funding (NIH, Velosano) and industry advisory roles create potential for framing bias
• No effect sizes or confidence intervals cited for clinical claims (the >80% threshold is presented as a cut-off without clear citation of the underlying RCT or cohort evidence in the abstract)
• "Views and reviews" label in journal — this is explicitly opinion-adjacent
• No breakdown of which studies support abandoning immunosuppression: how many trials, how large, what outcomes

Strengths

• Addresses a genuinely underserved topic: ASA affects millions of infertile men but is rarely discussed in mainstream coverage
• Clinically pragmatic framing — directly addresses the IUI vs. ICSI decision, which is high-stakes and expensive
• Authored by specialists at a high-volume reproductive urology center with hands-on clinical experience
• Correctly identifies the obsolescence of immunosuppression, a point still poorly disseminated outside subspecialty circles
• Provides a decision algorithm that, if evidence-based in the full text, has real clinical utility

Verdict

This review won't change the field — it's a narrative synthesis, not new data — but it does a useful job codifying where the evidence currently lands on antisperm antibodies. The abandonment of corticosteroid immunosuppression and the stratification of care around the >80% binding threshold are the key takeaways. What the abstract doesn't show is how rigorously the full text defends those thresholds; without seeing the evidence tables, the algorithm is expert opinion dressed as protocol. Worth reading for reproductive urologists who need a concise clinical framework, but not a paper to cite for efficacy claims.