When I was aged 5-6-7, in the early 1960s nobody would tell me what caused some women to produce babies whilst others did not.
Eventually from months of observation of neighbours, parents' friends, schoolfriends' parents, teachers, shop assistants and my own family, the royal family and famous actresses on the news, and even by observing women in films and tv programmes, I worked it out all by myself.
It wasn't to do with being in the company of men, because women casually dating did not get pregnant.
I deduced that there was only one thing that it could be: a wedding ring, worn on one specific finger. I noticed that unmarried women wearing decorative rings avoided putting them on that "magic" finger, and sure enough they did not get pregnant.
A ring was the only difference between the women who became pregnant and those that did not.
And THAT explained why there was no much emphasis on a man going out and buying a ring and putting it on a woman's finger - it meant he wanted her to start having babies! And a wedding ceremony was a ritual in which he put that magic ring on her finger, knowing that it would start the first pregnancy.
Further pregnancies were random, but could only happen if the ring was worn. I noticed that a woman we knew who had divorced her husband removed her ring, and, sure enough, she had no more babies!
I had two theories as to how the ring caused pregnancy. It could be that wearing the ring on one specific finger applied pressure to a specific spot on the skin, which caused random pregnancies, or it could be that, when a lovey dovey couple held hands, which I noticed they did a lot, the man was actually doing something to the ring, like rubbing it, or pressing it against her finger, to make her pregnant.
I noticed that love songs on the radio often mentioned a man taking a woman's hand (there was one by Elvis).The Beatles "I wanna hold your hand" was about a man's desire to make his wife pregnant by rubbing or pressing on her ring.
I had a seecond theory: pregnancy may have been caused by a chemical reaction to gold; after all, people always said a wedding ring HAD to be gold, and this would explain why.
I felt very smug and clever to have worked it all out for myself! I held this belief until we had sex education at school when I was 9 or 10.