Maybe it's not the bare minimum? Maybe they had limited funding, largely access only to "Western sperm" (which actually is a reasonable category I would argue because we share a lifestyle to a greater or lesser degree), maybe they had sparse data that covered simply "not the West".
If they had access largely only to "western" sperm then they could separate it out by country, or income, or something more sane. It's not like the rest of the world shares a lifestyle!
