Depends on the fish. If its a Goldfish, Zebra Danio, cichlid, betta or others like them then yes, but mollies, platys, Guppies, and many others are live bearers and the fry are born free swimming....
When the female lays her eggs the male will come and fertilize them so that they can become babies. Or if the female does not want that she'll scare away the male so that no babies can be made.