Okla. Stat. tit. 10, § 557.8

A. A gestational agreement that is not validated as provided by the Oklahoma Gestational Agreement Act is unenforceable except to the extent expressly provided by this act. B. The parent-child relationship for a child born as a result of an assisted reproduction procedure under a gestational agreement that is not validated as provided by this act is determined as otherwise provided by Oklahoma law. C. A gestational agreement that has not been validated shall nonetheless be enforceable to the extent it requires any party under such gestational agreement to pay for or to reimburse any other party for any medical, legal or travel expenses incurred pursuant to the gestational agreement.