I agree with other posters - obviously you want to be respectful towards your parents, but you are an adult and you're married. When I told my mother, I followed it up by saying "I respect you and want to hear your thoughts on this, but just so you know, it doesn't change my decision" and she respected that.
Also, get your parents more involved and educated on the procedure itself. Most times the negativity/fear comes from lack of knowledge. Knowledge really is power lol