I was born with 6 fingers and 6 toes on each hand and foot. All had bones and nails and all were removed before I was 1. Its something that runs in my family, so I dont think it came as much of a surprise to my family. It stems from my mothers side and goes back quite a number of generations. I am VERY glad that my parents had them removed, the scars dont get noticed unless i show them to people and both my hands and my feet look practically normal. The only thing different is that my little toes on my feet are slightly further down than they should be and slightly small, but it just looks like i have unfortunate feet....i never wanted to be a foot model anyway! I also have extra bones in between my fingers and toes. The only reason I know this is because of an xray on my feet after an injury.
I would say that removing them at an early age is a very good idea. It means that your child can wear gloves and normal shoes Also if you left on the extra toes until they are older their centre of gravity will need to change so if they are removed before they start to walk or relitivly young anyway this doesn't pose such a problem.
I am 5 months pregnant with my first child and will find out if it has extra digets at my scan next week. I hope not, but wont be worried if it has because if you look at my grandmothers hands and feet and then my mothers and mine you can see how advanced the removal is becoming. Im sure it is barely noticable now than it was 25 years ago when mine were removed and 49 years ago when my mothers were and lots and lots of years ago when my grandmothers were!!!!
Hope this helps!