If you are in the country or having treatment, a donation treatment, in a country that the doctor needs to select the donor for you or must according to regulations, then what they usually do is take a full characteristics of both intended parents and then try and match to the phenotypic characteristics of the donor as much as possible, for example, hair colour, eye colour, skin tone and the body build. These will, of course, be quite subjective and therefore there is an element that may or may not lead to the same characteristics you would expect in the baby.
Choosing a donor can be based on different aspects. Taking for granted that everyone follows the regulations we can have different criteria to make this decision. As you can imagine, the decision could be based on lab operations. But it could be based on genetic compatibility or facial resemblance that can also help make the decision.
If we already have a pool of donors that are phenotypically similar and are genetically compatible, why shouldn’t choose the one with the best facial resemblance? Tools like Fenomatch can help with this last task. This tool measures more than 12,000 facial biometrics at the same time and helps doctors and embryologists base their decision of choosing a donor based on scientific arguments.
