Is It Dangeorus To Delay Cesarean Section To Remove Dead Fetus?

My niece was diagnoised with placenta previa and experienced some bleeding she was told that if she could carry another month the baby would be viable. 3 weeks into this period she had a scan and it was discovered that the baby had no heart beat and was dead, she is now being told she must wait 7 days till they do a cesarian to remove her dead child, other than the obvious mental anguish are there medical problems that could be associated with waiting so long? Thank you An Aunt in Anguish