Changes in Male Testosterone Levels over the Last Century As Reflected In Facial Width-Height Ratios

Purported changes in male fertility and testosterone levels over the last 50 years remain controversial. The present study addressed this issue indirectly via a facial metric, the bizygomatic width-to-height (FWH) ratio, which has been shown to be reflective of testosterone levels. FWH ratios were assessed from photographs of Major League Baseball (MLB) players dating back to 1870. There was a progressive increase in FWH ratios over the past 120 years which was independent of height. FWH ratios, weight and BMI increased more after WWII than before. The results do not support an inference, based on declining sperm counts, that testosterone levels have declined.