Ryan Gosling & Eva Mendes -- The Cover Up Is Over ... We Just Had A Baby!

Ryan Gosling and Eva Mendes are now the proud parents of a baby girl -- which is damn near miraculous, considering they denied she was pregnant all along.

Eva popped out the little bambina on Friday ... according to US Weekly.

So far ... Ryan and Eva haven't revealed a name or any of the baby's vital stats -- which is not shocking. As recently as July they wouldn't cop to the pregnancy ... even after Eva was photographed clearly trying to cover her belly.

Little girl's got the most gorgeous parents on the planet -- c'mon ... we gotta see the baby.