Sorry but I think some of the comments here a bit ridiculous!! Having a child in your 40's is increasingly common, and certainly doesn't mean you're "grandparent age" 😂😂. Nor does it mean that you will have a "severely disabled" child. I wish people would be factual rather than knee jerk about these things.
OP - While I don't agree with the "it's impossible" camp, it is less likely, and there is an increased chance of complications. Assuming you still have regular periods, then you are still ovulating and therefore can still become pregnant. However over the age of 45 the likelihood of this happening is medically quoted as 10%. You also have to consider that if you did become pregnant, it will be a lot harder and take considerably more out of your body than your previous pregnancies. And you have to consider that it's not just pregnancy and childbirth, having little ones is exhausting, are you really sure you want to go through all of that again?
As someone above has said, have you explored the reasons why you are feeling this way? It's completely natural to feel pangs of regret when our baby-making days are coming to an end, I still get broody when hold a new baby - similar age to you - but I don't think I'd want to put my body through that again, as much as part of me loves the idea!!
If you're set on this then it's entirely your choice to try, but please be realistic about your chances, as medically they are low, and there is an increased risk of miscarriage, which is not something I'd wish on anyone. Do make sure this is really what you want. Lots of luck to you xxx