Stem Cells as New Agents for the Treatment of Infertility: Current and Future Perspectives and Challenges

Table 2

Potential advantages and disadvantages of stem cells in regenerative medicine.

Stem cells	Advantages	Disadvantages
ESCs	Pluripotent; high telomerase activity	Ethical concerns; malignant potential; difficult to control; may require many steps to differentiate into desired cell type; immune rejection
MSCs	No ethical or moral concerns; low malignant potential; avoiding allogeneic immune rejection	Limited flexibility; multipotent; difficulty to be maintained in cell culture for long periods
Stem cell from extraembryonic tissues	No ethical or moral concerns; reducing risk of tumorigenicity	Limited flexibility; multipotent
iPSCs	No ethical or moral concerns; patient-specific cells	Use of viral vectors to introduce genes; malignant potential
Spermatogonial stem cells	No ethical or moral concerns	Relatively small numbers in testis; difficulty to be maintained in cultures; immune rejection