What is the process of in vitro gametogenesis?

Three main techniques for creating IVD (In vitro derived) gametes have been described in the literature. The primary difference among these techniques relates to the source of stem  cells  used  to  derive  the  IVD  gametes.  These  sources include

1. induced pluripotent stem cells
2. embryonic stem cells (ESCs) from cloned embryos
3. ESCs from in vitro fertilization (IVF) embryos.

Creating IVD gametes from induced pluripotent stem cells (iPSCs) involves genetically reprogramming a somatic cell  (e.g.  skin  cell)  from  one  of  the  prospective  parents  to become  iPSCs,  and  differentiating  these  iPSCs  into  IVD gametes, which can be combined with other IVD gametes (or non‐IVD gametes) in vitro. IVD gametes can also be created from ESCs taken from cloned embryos created using somatic cell nuclear transfer

Finally, IVD gametes can be derived from ESCs taken from embryos created through IVF. This approach avoids some of the technical challenges associated with the other two methods. The IVD gamete from one prospective parent would be combined in vitro with a non‐IVD gamete from the other prospective parent.