Gall anymataliaeth ysgarthol effeithio ar unrhyw un.  Y grŵp mwyaf yw menywod, ifanc a hen, oherwydd y cysylltiad â beichiogrwydd ac anaf obstetrig. Fodd bynnag, mae llawer o achosion eraill, gan gynnwys llawdriniaeth am ganser a radiotherapi sy'n effeithio ar ddynion a menywod.
Faecal incontinence (FI) can affect anyone. The largest group is women, both young and old due to the association with pregnancy and obstetric injury. However there are multiple other causes, including surgery for cancer and radiotherapy which affect both men and women.