i use to think that everyone had a period. but now i know that only girls have them.
A childhood belief about periods

others believed things like this
- I thought that the difference between girls and boys was that girls have teeth.
Anon - I used to believe all babies came out as girls and later on in life some of those girls turned into boys — Tom
- I used to believe that you had to be on your period to get pregnant........— Tricia
- HA! I used to think when you got your period, you would just pee blood...I wish it was like that...if only.Anon
- i used to think that had to wear diapers when you were on your period— Jess
- I used to believe that if you went swimming after you got your first period, then you could get pregnant. — Mel