I used to think that the number of babies a woman would have was programmed into her -- there was no external factor like sex that would 'make' a baby, it would just happen randomly. ...at least until it occurred to me that dads were important somehow; then I thought it was kissing that made babies.
A childhood belief about reproduction

others believed things like this
- When i was little I thought babies were made by french kissing. havn't you ever seen look whos talking now?!
— randa - i used to believe that babies were made out of spit from people kissing too much, lol.— ecila
- I thought baby oli was made from pressed babies.Anon
- I used to believe that to make babies, a man would pee into a woman's butt. There. I said it.— Hu Flung Pu
- My friend used to believe baby oil was made from babiesAnon
- I used to think that babies were made when you press your mums belly button.
Then a baby would fall out— Chris Hyndman