Of course I would try to talk anyone I knew or loved out of doing something like this. As I said, I don't agree with having it done, nor do I think if I were a surgeon that I could perform the procedure in good conscience. However, me disagreeing with something does not make it "wrong". I cannot make that choice for another person, and as I said, it doesn't necessarily make someone mentally unstable if they want such a procedure (it doesn't automatically grant that they are NOT unstable, either - I am just saying that I am not in a position to tell others which procedures they may and may not have).
Plenty of people have died from less invasive and more "routine" plastic surgeries. ANY procedure that puts you under general anesthesia is a risk, but it seems hypocritical to say one elective procedure is allowed while another is not. There are all sorts of unusual surgeries being performed all over, from removing muscle to make legs less "bulky" to shaving down bone to make a face look "finer". There are even procedures to attempt to lengthen long bones to make legs longer. I would not want to have or want anyone I loved to have ANY of these procedures. But I am not sure I trust you, me or anyone else to have the final say about which procedures are okay and which are not.
As for the 76 year old mother of a young child, let me just say that I'm glad it isn't me! But men get to make the decision to be an older or even a "too old" parent all the time. Again, just because it is possible doesn't mean it is a great thing to do. I guess a person would have to ask the child whether he was happier to have been born at all or not, but unfortunately children have no say in the circumstances of their birth.