A major ethical concern around stem cell research is the manner in which stem cells are harvested from oocytes and embryos. This debate centers around the idea of personhood and at which stage of life an embryo is considered to be a human, explains EuroStemCell.
As of 2015, scientists have recently developed methods to reprogram somatic cells to produce pluripotent stem cells, according to PubMed. This eliminates the need to harvest stem cells from an embryo and removes a major ethical concern about human stem cell research. Other ethical concerns that still remain include patient consent to donate tissue for human stem cell research, the first clinical trials for human stem cell therapies, and managing oversight of new stem cell developments.