Sometimes I talk with people for whom the most important thing in a donor is that she be Jewish. Sometimes it's faith and tradition, sometimes it matters to the extended family (who may be helping finance the journey), and sometimes it's so the child will be "as much like me as possible".
Everyone has their own legitimate reasons.
When it comes to a Jewish donor, there are two notes worth paying attention to:
A. Availability and costs of egg donation from a Jewish donor
First — Jewish donors exist. Some even hold official certificates and documents proving their Jewishness, and those documents may serve you in the future. Some donors are simply Jewish women who never attached importance to their Jewishness, and it's not certain they hold official documentation that would satisfy the authorities in your home country.
There are egg-donor databases that specialize in Jewish donors and know what needs to be provided legally. In regular databases too (clinics' databases, for example) a Jewish donor sometimes appears — but it's less common, and not something to count on.
B. Genetics
Without getting into the emotional considerations of choosing a Jewish donor — some will actually advise you to "mix" the genes. Out of custom and tradition, we married and had children within our small, closed communities. Over the years, that custom is why there are genetic diseases we recognize today among Jews (as in other communities that did the same). So from this angle, it can actually be a good thing to choose a donor who grew up in a different community.
