Worldwide Temporal Trends in Penile Length: A Systematic Review and Meta-Analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-regression of non-randomized observational studies
PubMed 36792094 · doi:10.5534/wjmh.220203
What was done
A systematic review and meta-analysis was conducted across PubMed, Embase, and the Cochrane Library through April 2022 following PRISMA guidelines. The authors pooled means and standard deviations for flaccid, stretched, and erect penile length, assessed subgroup differences by region, population type, and decade of publication, and performed metaregressions to adjust for potential confounders.
What was found
Analyzing 75 studies published between 1942 and 2021 comprising 55,761 men, pooled mean estimates were: - Flaccid length: 8.70 cm (95% CI, 8.16–9.23) - Stretched length: 12.93 cm (95% CI, 12.48–13.39) - Erect length: 13.93 cm (95% CI, 13.20–14.65) Measurements varied significantly across geographic regions. Erect penile length increased significantly over time (QM = 4.49, df = 2, p = 0.04) across multiple world regions and all age groups, while flaccid and stretched lengths showed no temporal trends. After adjusting for geographic region, age, and subject population, erect length increased by 24% over the past 29 years.
Why it matters
This review compiles global reference data for adult penile dimensions and demonstrates a significant worldwide increase in erect penile length over the last three decades.
Limits
The findings rely on heterogeneous cross-sectional studies spanning eight decades, introducing potential confounding from changing measurement techniques, varying examiner expertise, and sampling differences over time. Underlying causes driving the temporal increase were not directly investigated or measured.
Cited by
- supports The average erect human penis length is between 5.3 and 5.5 inches.