question on 700 yr old aging process

[Plenum]

this may seem like a silly/flippant question, but here goes.

let us say that we had the 'normal' ageing process for 3rd density. That is, we lived for 700-900 years.

what would ageing look like?

I mean, would you still become an 'adult' at age 20, and then 'slowly' age over the next 600 years, going through the same physical changes as a 20-60 year old, but just over a longer span?

and what would reproductive cycles be like for women? I mean, could a woman become a mother of 400 kids?? it would seem not, because the populations back then stayed very low, but would it be possible, if such a woman wanted such a thing???

thank you kind forum for your indulgence in these idle questions.