First things first, masturbation by definition is the" sexual stimulation of one's own genitals, to the stage of reaching orgasm". It has been documented in both sexes and of all age groups, but with variation in frequency and prevalence.
There is however, the risk of using foreign objects and inserting them in one's own genitals or anus, and getting them "stuck". Every Emergency Room must has its share of similar accidents.
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