Yup. I’ve told y’all this before, but I remember as a child seeing the neighbor’s dog in a “diaper” every now and then, and our own female puppies leaving blood spots on the floor before we got them spayed.
I absorbed the message that the bleeding was a sign of being in heat and the diaper was to help ensure she didn’t get mated if they didn’t want to deal with puppies.
That was about all the information I was directly given concerning menstruation, and I remember when I learned about unwanted pregnancy as a middle-schooler, I thought “Well for goodness sake, why are some people so careless? Just avoid sex for a while once you “go into heat” when the menstrual bleeding starts, and you’re guaranteed not to get pregnant! Couldn’t be simpler!”
Fortunately, I had a seventh-grade sex ed class that clarified the time lag between menstrual bleeding and ovulation in the human, as opposed to canine, reproductive system, so I knew not to rely on my original assumptions about “natural fertility control” once I was old enough to test those hypotheses in practice.
But I have to wonder how many inadvertently pregnant girls and young women who grew up around pets and/or livestock made exactly the same natural but erroneous deduction that I did.