Is it okay to hide pregnancy from your parents?

I am just curious on your opinions. Whenever i do succeed in TTC I don't want to tell my parents right away. I dont want them to look down on me, or hate my fiance for getting me pregnant. For some reason this isnt stopping me from trying. I just know my mom would flip out and scream and cuss me for getting pregnant, and Im dad would do the same if not worse. Im afraid of them hating my fiance too. I just wish my parents were like my fiances and would be happy. And how long can/should i hide from my parents? Im also afraid they would force me to get an abortion. Help!