I cannot help but feel that more specific detail is needed for this topic. Exactly what are you required to write about the topic? I think that several thesis statements can emerge quite nicely once this is clearly established. On one hand, I believe that being able to talk about how adoption is more common now than it was about ten or twenty years ago would be one approach to take. Adoption is not something seen as taboo or even "different" as much as it used to be. At the same time, it might be interesting to focus on the issue of international adoption and how policies and practices in this realm have changed over the last two decades. The pursuit of international adoption has increased with fervor, but is also matched up with greater regulation and requirements that need to be met. I think that discussing how some parts of the world still hold adoption in a light that is not concurrent with the wider embrace of it might be another area to address. All of these seem to me to be very viable options, but I think that all of them are held hostage to more specificity on the topic and from this, a thesis statement can be developed.