First of all, I doubt whether you can get the reversal on the NHS ~ so you may have to fork out quite a few spondooliks in the private sector..for something that has got around a 50% success rate if the original operation was the method using clips.
I think this is the reason the doctor wants you to be sure you are certain you want the operation in the first place...
Go to your GP and ask their advice, as they will have all the info you need :o)
i was told it couldn't be reversed and if i changed my mind, the only thing i could do is have IVF whihc i would have to fund, so yes you def need to speak to your doc, good luck anyway