Multifactorial determinants of male genital measurements: Correlations of stretched penile length and anogenital distance with anthropometric parameters.

Abstract

Background: The stretched penile length is recognized as the most reliable measure of true penile size, this fact is not widely acknowledged, and societal myths often associate penile length with other anthropometric measurements. While markers of prenatal androgen exposure, such as anogenital distance and the second-to-fourth digit ratio (2D:4D), have been widely studied, there is a lack of exploring the specific relationship between anogenital distance and stretched penile length in adult males.

Objective: This study aims to investigate the relationship between stretched penile length and anthropometric measurements. Additionally, it examines the correlation between stretched penile length and anogenital distance.

Materials and methods: The study included 1312 healthy males aged 18-22 years who visited a urology clinic for non-genital problems. Anthropometric measurements were collected. Anogenital distance was measured as the anoscrotal distance. The anthropometric indices were calculated using established formulas. Data were analyzed using univariate and multivariate regression models.

Results: Anogenital distance emerged as the strongest independent predictor of stretched penile length (β = 0.618, p < 0.001) in the multivariate analysis. Fourth digit length also showed a significant association (β = 0.475, p = 0.042). Other anthropometric variables were not independently predictive of stretched penile length. Anogenital distance itself was significantly associated with stretched penile length, second-to-fourth digit ratio, and the crown-to-pubis distance.

Discussion: This study reinforces the clinical utility of adult-derived measurements such as anogenital distance, second-to-fourth digit ratio, and stretched penile length as reliable biomarkers of prenatal androgen exposure during the masculinization programming window. By demonstrating significant associations among these parameters, the findings highlight their relevance in assessing the impact of prenatal hormonal environments on male genital development.

Conclusion: This study highlights anogenital distance and stretched penile length as reliable key biomarkers for prenatal androgen exposure. The findings contribute to understanding male genital development and its implications for reproductive health. The results also dispells societal myths regarding penile size and anthropometric measurements.