Worldwide Temporal Trends in Penile Length: A Systematic Review and Meta-Analysis

• Authors: Federico Belladelli, University Vita-Salute San Raffaele; Francesco Del Giudice, University Sapienza; Frank Glover III, Emory University; Evan Mulloy, Stanford University; Wade Muncey, Stanford University; Satvir Basran, Stanford University; Giuseppe Fallara, University Vita-Salute San Raffaele; Edoardo Pozzi, University Vita-Salute San Raffaele; Francesco Montorsi, University Vita-Salute San Raffaele; Andrea Salonia, University Vita-Salute San Raffaele; Michael L Eisenberg, Stanford University
• Journal Title: The World Journal of Men's Health
• Volume: Volume 41, Number 4
• Publisher: Korean Society for Sexual Medicine and Andrology | 2023-02-15, Pages 848-860
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.5534/wjmh.220203
• Subjects: Health Sciences, Medicine and Surgery; Biology, Anatomy; Health Sciences, Public Health
• Keywords: anatomy; hormones; meta-analysis; penile length; sexual health

Abstract

Purpose: Normative male genital measurements are clinically useful and temporal changes would have important implications. The aim of the present study is to characterize the trend of worldwide penile length over time. Materials and Methods: A systematic review and meta-analysis using papers from PubMed, Embase, and Cochrane Library from inception to April 2022 was performed. PRISMA guidelines were used for abstracting data and assessing data quality and validity. Pooled means and standard deviations for flaccid, stretched, and erect length were obtained. Subgroup analyses were performed by looking at differences in the region of origin, population type, and the decade of publication. Metaregression analyses were to adjusted for potential confounders. Results: Seventy-five studies published between 1942 and 2021 were evaluated including data from 55,761 men. The pooled mean length estimates were flaccid length: 8.70 cm (95% CI, 8.16–9.23), stretched length: 12.93 cm (95% CI, 12.48–13.39), and erect length: 13.93 cm (95% CI, 13.20–14.65). All measurements showed variation by geographic region. Erect length increased significantly over time (QM=4.49, df=2, p=0.04) in several regions of the world and across all age groups, while no trends were identified in other penile size measurements. After adjusting for geographic region, subject age, and subject population; erect penile length increased 24% over the past 29 years. Conclusions: The average erect penis length has increased over the past three decades across the world. Given the significant implications, attention to potential causes should be investigated.