Reference range for penile length measurements in Chinese men, and their relationship with somatometric parameters: a prospective analysis and establishment of a nomogram

Abstract

Objective: To establish a reference range and construct a nomogram for adult male penile size in the Chinese population, and to investigate relationships between penile length and various somatometric parameters. Patients & Methods: Men who required surgery under general or spinal anaesthesia were recruited (January 2018 to June 2019). Patients with history of penile deformities were excluded. Standardised, validated penile measurements were recorded. Correlations between penile length and somatometric parameters were assessed (Pearson’s analysis). Results: 404 men were eligible. Mean age 66.4 years. Mean flaccid pendulous length, pubic arch penile length, stretched flaccid length and flaccid circumference were 9.29 cm, 10.9 cm, 12.5 cm and 7.97 cm respectively. True micropenis was 7.49 cm (2.5 SD < mean). Flaccid circumference was positively correlated with BMI (r = 0.26). Obese men (BMI ≥ 25) had significantly shorter flaccid pendulous length than non-obese men, (8.96 cm vs. 9.50 cm; p = 0.015), although their stretched flaccid lengths were similar (12.5 cm vs. 12.8 cm; p = 0.217). Conclusion: We established a penile length nomogram in Chinese population. This will help counsel patients with penile length concerns or require penile surgery. Weight loss can be advised to increase flaccid penile length.