Womb carrying folks usually start menstruation (i.e. regular periods) before the age of 16 years*. I was much older than this when I began to accurately understand what my anatomy ‘down there’ was like. I think I had a conception of tampons being a cross between a plug and a sponge. I guess this isn’t completely wrong, but neither is it completely right as the bleeding’s coming from the cervix, with a vagina being a passage way.
I’ve come across a fair few people who have an aversion to using tampons, partly because they are not confident (or downright uncomfortable) with their anatomy and with the idea of placing something in to their vagina. Even amongst some of my liberated friends, I am considered a bit of a fringe eccentric for using a mooncup – something I’ve done of the last few years. About the size of an egg cup and made from soft silicone, it sits in the vagina, just below the cervix and catches blood. It can then be washed, without contributing plastic to the bin or cotton to sewage waste.
n.b. I’ve recently discovered that ‘mooncup’ is just one of many other brands. This has somewhat blown my mind.
*Lawrence and Impey (2012) Obstetrics and Gynaecology, 4th Ed.