This kind of planning implicitly happens when women are expected to have a career instead of finding their identity in successful motherhood. I don't know much

This kind of planning implicitly happens when women are expected to have a career instead of finding their identity in successful motherhood. I don't know much anything at all about Korean women's professional labor, but I'd be very surprised if it did not play a role. Country fertility rates correlate extremely well with female full time non domestic labor participation.