If you are on HRT, it is less impossible. A couple of the recorded women who got pregnant spontaneously in their 50s were on hormone replacement therapy.
Possible, especially if you have had a lot of other kids. Rare, for sure. You do need to be on birth control as long as you are having periods.
It is still possible! Yes rare, but deff possible if you still get your period. If you miss your next period, take a test just in case. My friends mom is 43 with a 1 year old :)
It would probably be rare at your age. You should be going through menapause by now.