The female triad is a collection of 3 separate yet interrelated conditions of low energy availability (due to disordered eating), menstrual disorders (irregular or absent menstrual periods) & reduced bone density (osteoporosis or osteopenia). It is considered part of the broader, more comprehensive & gender non-specific Relative Energy Deficiency in Sport (RED-S).

If an athlete is suffering from one element of the triad, it is likely that they are suffering from the other two components as well. It is recognized that the independent effect of each condition is serious but when combined is potentially lethal.