Background and Objective: The constant phi number (1.618…) is accepted as the indicator of esthetic beauty and harmony in numerous fields of natural sciences and is also known to be effective in various biological systems in the human body such as skeletal system and facial anatomy, respiratory system, and cardiovascular system. In this study, we aimed to compare the anthropometric proportions obtained from penile measurements and the phi-value and to investigate whether this number could be an indicator of fertility.

Material and Methods: This study included 200 infertile male patients. Penile ratio (PR) was calculated by dividing the corpus penis length by the glans penis length. Patients were divided into two equal groups: Group-I included patients with a PR that was closest to the constant phi-value (n = 100) and Group-II included patients with a PR that was the most distant to the phi-value (n = 100). Spermiogram findings, and serum hormone levels were compared between the two groups.

Results: Mean age was 27.37 \pm 3.45 years, median penile length was 9.1 (7.1-10.2) cm, and median PR was 2.06 (1.65-2.64). In group I and II, an abnormal spermiogram was detected in 41% and 48% (P = 0.319) and hormonal dysfunction was present in 28% and 26% of the patients (P = 0.750), respectively. Overall sperm counts and sperm concentrations were significantly higher in group I compared to group II.

Conclusion: Although PR may not be an indicator of normal spermiogram or hormone status, patients with a closer PR to the phi value are likely to have more favorable spermiogram values.