In industrialized countries, such as the United States, South Korea, and parts of Western Europe, the average age for menarche is generally between 12 and 13 years, although it can occur as early as 8 and as late as 16 or 17.
आफ्रिका व आशियाच्या काही भागात पाळी सुरू होण्याचे सरासरी वय थोडे जास्त आहे.