I have trouble getting my head around someone making it to term without realising too. I think though that it has been drilled into me since I was bout 8 years old that if you have sex there is *always* a chance you could be pregnant...So if I felt off, not quite right, strange feelings inside me, then period or not, contraception or not, it would always be one of the first things I would consider, at least to simply tick it off the list. I would also expect it to be one of the first questions a care provider would ask me, or any woman, with unexplained symptoms.
I'm not going through menopause - or old enough to assume I am, or having any fertility issues to make me question my ability to conceive either.