Why not say period?

[HotDiggidy2017]

Just wondering why we all use the abbreviation AF rather than just say period? Genuinely interested as I don’t think there’s much time difference in typing and surely a period is not a rude word in this day and age?

AF- long standing slang, not compulsory to use it. The expression “Aunt Flo visiting” was in use long before Mumsnet.

All the slang is from the early days of forums from what I gather. That's why it's called DTD /BD for instance cause the word sex would get you banned.