Use of Anabolic-Androgenic Steroids and Male Fertility: A Systematic Review and Meta-analysis.

BACKGROUND: Anabolic-androgenic steroids (AASs) are often used by men for bodybuilding and to improve sports performance. The use is not limited to professional competitive athletes, but many amateur men.

OBJECTIVE: The objective of this study was to assess and systematically review the effects of AAS on male fertility parameters, spermiogram, testosterone, follicle-stimulating hormone (FSH) and luteinising hormone (LH) and to review reversibility and other morbidity impacting fertility.

METHODS: Eligibility criteria - We included studies mentioning data about adult males using supraphysiologic doses of AAS for sports performance or appearance enhancement, with comparison data from general population or matched controls if available reporting fertility parameters and sexual performance. Information sources - A systematic literature search was performed using PubMed, MEDLINE, EMBASE, Google Scholar and World of Science. Controlled clinical trials randomised or nonrandomised (if available), case series with or without matched controls, case reports, cross-sectional surveys, reports on follow-up of subjects caught in doping test and their fertility parameters when reported. Risk of bias/quality assessment - The quality assessment of the included studies was performed using the Newcastle-Ottawa Scale.

RESULTS: Included studies - Thirty-two studies were included. There were 12 cohort studies, 5 case-control studies, 9 cross-sectional surveys and 6 case reports. The study population comprised 9371 individuals, of which 2671 were AAS users. Synthesis of results - AAS users had reduced levels of FSH and LH than the naïve population. These levels remained low for 3-6 months after stopping AAS. One year after stopping AAS, the users and naïve population had insignificant differences in FSH and LH values. The total testosterone (TT) levels were comparable in users and naïve populations at baseline, 3 months and 6 months after stopping, but at 1 year, TT values were lower in AAS users. Sperm concentration in AAS users and naïve population was similar, but sperm motility was lower in AAS users. The testicular size was lower in AAS users. The erectile function improved with AAS use, but on withdrawal, there was decreased libido and erectile dysfunction. Most AAS users need additional medications to mitigate detrimental effects on fertility. Description of the effect - AAS use negatively impacted the gonadotrophin levels and had lower sperm motility and testicular size. Strength - Comprehensive review of 32 publications, study population of 9371 individuals, of which 2671 were AAS users, meta-analysis of reproductive hormones, semen parameters and testis size.

LIMITATIONS: The limitations are small sample size of most of the studies, polypharmacy, lack of information on dosing and high heterogeneity.

INTERPRETATION: AAS use is detrimental for sperm motility and has a partially reversible negative impact on male fertility. Users must be cautioned about its negative impact on libido and erectile function. Registration: PROSPERO Registration No. CRD42023411294.