"officially" I was nearly 23 when I started.
"Unofficially" I actually started a little younger than that - let's say at 21... (I'm cetainly not recommending that course of action to anyone by the way, but back then, although more difficult to obtain, the dangers of self med were not nearly as well understood.)
As regards size, as I said it's a lottery - some of us get big other don't. If your mother was big then you may well follow suit.
It may also have been partly the result of being partial androgen insensitive. - But the bottom line is you can't guarrantee anything in life.
I don't think I would have "chosen" to be so big - but bear in mind that with a larger frame size that most of us have the size isn't nearly so noticable as it would be on the average 34inch female chest size. I'm a 38G / 40F depending on the bra - The only "problems" I have had over my size is that bras have to be underwired to give enough support and the larger sizes (above D) are more expensive. Also you have to be a lot more careful if you are going to do any "impact" sports like running because it can be uncomfortable if you don't get the right sports bra.
Overall it's not something that worries me at all.
