conducted by L.R. Setty in the 1960s defines 15 patterns of chest hair. In this study, four parts of the chest in which terminal hair occurs were identified: Chest hair may occur on each of these areas independent from the others, making for a total of 15 combinations in addition to the apilose (bare) pattern. Hair is said to occur on both the pectoral and circumareolar areas when there is hair around the nipples and on the breast, but these areas are not connected. The pecto-sterno-infraclavicular pattern, in which the breast, sternum and medial end of the clavicle is covered with terminal hair, is most common (57%). Examples of patterns See also Abdominal hair Hair References Further reading Secondary sexual characteristics Human hair