puerperium UK /ˌpju.əˈpɪə.ɹi.əm/US /ˌpju.ɚˈpɪɹ.i.əm/ noun1 •The period of time lasting around a month immediately following childbirth, when the mother’s uterus shrinks back to its prepartum state.As exciting causes, psychic traumata, exposure to cold, the puerperium, excesses, have been brought forward. — 1921 formspuerperia