Researchers do not know the cause of PGAD, but assume that it has neurological, vascular, pharmacological, and psychological causes.[1][4] Tarlov cysts have been speculated as a cause.[3][8] PGAD has been associated with clitoral priapism,[9] and is sometimes considered to be the same as priapism in men.[10] It is also similar to vulvodynia, in that the causes for both are not well understood, both last for a long time, and women with either condition may be told that it is psychological rather than physical.[3] It has been additionally associated with restless legs syndrome (RLS), but a minority of women with PGAD have restless legs syndrome.[6]