Ten heart failure patients receiving fetal stem cell injections are all showing signs of rapid recovery three months after the treatment. Earlier successes had been demonstrated with cells taken from bone marrow, but the fetal cells appear to be more effective with the change observed in fetal cells in one week matching that observed in autologous cells in three to four weeks.
The use of fetal stem cells would appear to be licit morally if they are donated by consenting parents who experience spontaneous miscarriages (somebody correct me if I'm wrong):
The bodies of the dead must be treated with respect and charity, in faith and hope of the Resurrection. ...Of course, restraint is necessary because
The free gifts of organs after death is legitimate and can be meritorious.
[Catechism of the Catholic Church, 2300-2301]
[i]t is morally inadmissable directly to bring about the ... death of a human being, even in order to delay the death of other persons.