They say, "when a child is born, so is a mother." Presumably, that applies to fathers too, but, since the journey for men is significantly less arduous, I'm not too sure. Watching a woman transition from the ripeness of her maternity to become the nurturing personification of compassion by holding a newborn isn't really work. However, being the hormonal, hemorrhoid-ridden, inflatable end of that equation is work.
Men go through their transition too. On the paternal end, the main point of development is sparked by the realization that you're destined to embody at least one element of your dad. The sooner you make peace with that, the better. In the video linked above, stand-up comedy heavyweight John Mulaney explains how he's becoming more like his father every day. Above all, he elucidates why he finds the process exhilarating both personally and professionally. Considering that Mulaney and Olivia Munn just became parents for the first time a few weeks ago—and the interview is a couple of years old—it'll be interesting to see how the comic frames his father in future specials. If you like getting a peek into the mind of a comedy master, give the video a watch.