I should think pretty carefully about whether I want to avoid putting music that I used to cope with the miscarriage onto my labor playlists. On the one hand, I used those songs to cope because they are incredibly powerful for me. On the other hand, maybe I won't want to hear them.

OTOH, you might be able to reclaim the songs if you hear them while you're birthing your baby. Maybe put them in a separate playlist and see how you feel in the moment?