preferred_name: Twin gestation, dichorionic/diamniotic (two placentae, two amniotic sacs)
preferred_name_lc: twin gestation, dichorionic/diamniotic (two placentae, two amniotic sacs)
label: Twin gestation, dichorionic/diamniotic (two placentae, two amniotic sacs)
label_lc: twin gestation, dichorionic/diamniotic (two placentae, two amniotic sacs)