ArticleInternational braz j urol : official journal of the Brazilian Society of Urology
Single-dose Tamsulosin Induces Reversible Azoospermia and Ejaculatory Dysfunction Suggesting Potential for on-demand Male Contraception.
Article in International braz j urol : official journal of the Brazilian Society of Urology. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeEjaculatory alterations are among the most frequent sexual side effects of α₁-adrenergic antagonists. Although often attributed to retrograde ejaculation, recent evidence indicates that tamsulosin primarily disrupts seminal emission, occasionally leading to transient azoospermia. This study evaluated the frequency, timing, and reversibility of ejaculatory and seminal changes following a single oral dose of 0.8 mg tamsulosin in healthy men. MATERIALS AND
methodsThirty-one healthy male volunteers (aged 18-45 years) underwent a baseline semen analysis, followed by six additional collections at 1-3 week intervals. Each collection was performed at a different post-dose time point, spaced every 4 hours, to construct a 24-hour post-administration profile. Semen parameters were assessed according to WHO criteria, and post-ejaculatory urine was examined to detect retrograde ejaculation. Temporal variations were analyzed using repeated-measures ANOVA, with effect sizes estimated by Cohen's d.
resultsSeminal volume decreased significantly in 93.6% of participants, with aspermia in 80.7%, peaking 12 h after ingestion (p<0.001, d=2.05). Sperm concentration declined markedly, with azoospermia in 80.7% (p<0.001, d=1.59) and normalized after wash-out in 2 days. No retrograde ejaculation was observed. Adverse effects were mild and self-limited. A single 0.8 mg dose of tamsulosin caused a consistent, time-dependent disruption of seminal emission, producing transient azoospermia rather than retrograde ejaculation.
conclusionsA single 0.8 mg dose of tamsulosin transiently suppressed seminal emission, leading to reversible azoospermia within 12 hours most recovered by 24h, and all recovered within 48h. Its predictable, reversible effect supports caution in men seeking conception and further exploration as an on-demand male contraceptive model.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.