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Metabolic & Cardiometabolic

anabolic-androgenic steroids causes testicular atrophy and impaired fertility

In plain terms: Do anabolic steroids cause testicular shrinkage and reduced fertility?

Strong support Metabolic & Cardiometabolic

Part of: 💊 anabolic-androgenic steroids

RefutedContestedStrong support
consensus score 1.00

Yes — steroids suppress the body's own testosterone and sperm production, shrinking the testes and often causing infertility; it usually recovers over months after stopping but sometimes incompletely.

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: Population patterns (Observational)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

9 support 0 contradict 0 tested null 0 mixed · 9 sources, 9 independent groups

The evidence (9)

SourceGradeStanceQualityFinding
Vorona
2018 · Minerva Endocrinol
observational supports moderate Review states AAS cause reversible suppression of spermatogenesis up to azoospermia via HPG-axis negative feedback.
Hashimi
2025 · Asian J Androl
observational supports high Review documents exogenous testosterone/AAS as a well-established cause of HPG-axis suppression, impaired spermatogenesis and azoospermia.
Sukegawa
2020 · Acta Urol Jpn
observational supports low Exogenous testosterone suppressed gonadotropins producing azoospermia to severe oligospermia, with variable recovery time after cessation.
Christou
2017 · Sports Med
observational supports high Systematic review and meta-analysis found AAS use markedly suppresses gonadotropins and spermatogenesis, reducing sperm concentration and testicular volume.
Kumar
2025 · Basic Clin Androl
observational supports moderate Testosterone/AAS abuse suppresses intratesticular testosterone causing impaired spermatogenesis, testicular atrophy and azoospermia, with prolonged or incomplete recovery.
Kanayama
2015 · Addiction
observational supports moderate Long-term AAS misusers frequently showed prolonged hypogonadism after discontinuation, an under-recognized reproductive consequence.
Rasmussen
2016 · PLoS One
observational supports moderate Current and former AAS abusers exhibited suppressed testosterone and hypogonadal symptoms, including reduced testicular function, persisting years after cessation.
Solanki
2023 · Endocr Connect
observational supports moderate Scoping review found testicular atrophy and suppressed spermatogenesis are expected after AAS abuse, recovering over months to years but sometimes incompletely.
Oduwole
2014 · FASEB J
animal supports moderate Exogenous testosterone doses that suppressed gonadotropins consistently blocked spermatogenesis in a knockout mouse model, supporting the fertility-suppression mechanism.

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