“…It is extremely rare among historic populations (following age adjustment), whereas in modern populations, HFI is a common phenomenon with a 5% frequency in males and 25% in females (Antón, 1997;Armelagos and Chrisman, 1988;Hershkovitz et al, 1999;Lazer, 1996;Moore, 1955). HFI etiology has not yet been fully clarified; however, previous studies have associated it with hormonal imbalance due to its high prevalence and severity in postmenopausal females, and the fact that only males with hypogonadism manifest advance stages of HFI (Hershkovitz et al, 1999;Moore, 1955;Perou, 1964;Ramchandren and Liebeskind, 2007;Yamakawa et al, 2006).…”