A couple of notes:
(1) If you regularly sell your eggs, it could be a business (self employment, and therefore eligible to contribute to a Roth IRA).
(2) If you are a full time student under age 24 and your total income from the egg donation is over $1050, reporting it as "other income" will result in requiring to file a tax return and likely owing tax. The $12,000 threshold would not apply in that situation.
