American Society of Hirudotherapy

Efficacy and Safety of Hirudotherapy for Improving Sperm Quality Parameters in Male Infertility: A Randomized Controlled Trial

Randomized controlled trial published in Health science reports (2026)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsGenomics & ProteomicsSalivary PharmacologySafety & Infection ControlAbtahi-Forooshani M et al. · Health science reports, 2026

Abstract

BACKGROUND AND AIMS: Male infertility, often characterized by impaired sperm parameters, remains a significant clinical challenge. This study aimed to evaluate the efficacy and safety of hirudotherapy (medicinal leech therapy) in improving sperm quality parameters in men with idiopathic infertility. METHODS: In this randomized controlled trial, 50 male volunteers aged 20-50 years were randomly assigned to either an experimental group receiving weekly leech therapy for 3 months (n = 25) or a control group receiving no intervention (n = 25). Semen parameters were assessed at baseline and after the intervention period. Evaluations included semen analysis according to WHO guidelines, sperm DNA fragmentation by TUNEL assay, protamine deficiency by chromomycin A3 staining, and assessments of sperm viability and morphology using flow cytometry and Diff-Quik staining. Statistical analyses were performed using SPSS version 21.0, with significance set at p < 0.05. RESULTS: Compared to the control group, leech therapy significantly improved several sperm quality parameters. Sperm concentration increased from 57.7 ± 17.1 to 63.4 ± 13.1 million/mL (p = 0.006). Total sperm count, progressive motility, and normal morphology also improved significantly (p < 0.05). DNA fragmentation decreased significantly in the experimental group compared to controls (mean difference: -3.9%; p = 0.04). Protamine deficiency also showed a significant reduction (p = 0.02). No adverse effects related to the intervention were observed. CONCLUSION: This randomized controlled trial suggests that hirudotherapy may improve sperm quality parameters, including concentration, motility, morphology, and DNA integrity, in men with idiopathic infertility. These findings support further investigation of leech therapy as a complementary approach to male infertility management. Trial Registration: IRCT20230502058045N.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article

Summary

Male infertility, often characterized by impaired sperm parameters, remains a significant clinical challenge. This study aimed to evaluate the efficacy and safety of hirudotherapy (medicinal leech therapy) in improving sperm quality parameters in men with idiopathic infertility.

Why This Matters for Hirudotherapy

This randomized controlled trial directly examined hirudotherapy, randomizing 50 men with idiopathic infertility to either weekly medicinal leech application for three months or no intervention, and assessed semen parameters per WHO guidelines along with sperm DNA fragmentation, protamine deficiency, viability, and morphology. The study reported statistically significant improvements in sperm concentration, total count, progressive motility, normal morphology, DNA integrity, and protamine deficiency, with no observed adverse effects. For the ASH domain, this trial is notable because it represents one of the few randomized clinical investigations of hirudotherapy in reproductive medicine, potentially expanding the evidence base for leech therapy beyond its conventional surgical and dermatological applications. However, important caveats apply: the sample size was modest, the control arm received no sham intervention (introducing possible placebo and attention biases), follow-up was limited to three months, and the underlying mechanism—whether via salivary anticoagulants, anti-inflammatory compounds, or other bioactive constituents—remains unelucidated. The findings are preliminary and require confirmation in larger, blinded, sham-controlled trials.

Citation

Efficacy and Safety of Hirudotherapy for Improving Sperm Quality Parameters in Male Infertility: A Randomized Controlled Trial.

Abtahi-Forooshani M et al. · Health science reports, 2026

Added to ASH library: March 18, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.