How do you tell your parents they're...

a friend of mine (she's now 21, has a two month old baby) went to her parents and was like:
"yeah, you won't believe me what happend (with a really dramatic face)-I went over to your car and realized it actually wasn't your car"
and her father was like "what-I thought you were pregnant or something like that"
and than she just said "oh yeah, I am pregnant, I almost forgot-I was so crazy about that car thing".

Her mother almost got a heart attack, her father just laughed and said he likes her way of humor.

My uncle went to my grandma at her birthday "oh, mom, ahm, I had no money to buy you something and was really busy
so I just impregnated my girl and got you a grindchild as a present-happy b-day!"

I think I won't be as funny.
 
wait until it's one of their birthdays and present it as a present...
like "you know how you always said you wanted rather something personal than something I bought? Well, this year I give you a new addition to your family....you can hug it and love it as long as you live....if that's not a present!"

you can't complain about a present

EDIT: fck, StefTD beat me to it!
 
you could like...watch "Alien" together, and at the chestbreaker scenes say something like
"oh, that kind of reminds me of something."
.
.
.
lame^^


but anyway, congrats!
 
My step-daughter told my wife and I over Christmas several years back by giving my wife a gift that contained a sweater she had made that had the words "World's Best Grandmother" embroided on the front. We were in the middle of opening gifts when all of a sudden my wife screamed and we all thought something was wrong; I looked over and saw my wife clutching this sweater and just looking over at my step-daughter with eyes open wide, tears running down her cheek, and jaw hanging down to her feet - it then turned into a smile and my step-daughter and her husband started laughing out loud. It was a very nice Christmas indeed.