This is my first tab, and may be wrong sometimes...anyway, i didn't found any tabs of 
music, and i just like it very much. So, i tried to put the things together :P...anyway, 
can fix things you realize that is wrong.

Intro Bb5

Bb5
You skipped the foreplay
And now the baby's on its way (and in the "duru" part play C5 D#m5 Bb5)

Bb5
You swear you don't know
As her belly grows and grows C5 D#m5 Bb5

Bb5
Oh you thought it was a gift
When she asked you for a lift C5 D#m5 Bb5

   D#m5  F5
La la la la la la la
D#m5  F5
La la la la la la
D#m5  F5
La la la la la la

And the rest is the same thing...hope you enjoy :)