Iowa Code § 57.2
If notice of a contest of the election of an officer is filed before the certificate of election is delivered to the incumbent, or notice of a contest of the declared result of an election on a public measure is filed before a duplicate of the abstract of votes upon the measure and of the county board's declaration is certified pursuant to section 50.27, the certificate or duplicate abstract and declaration shall be withheld until the determination of the contest. If the certificate of election or duplicate abstract and declaration have been issued, the commissioner shall send the persons or political subdivisions affected by the notice of contest a statement advising them that the election is being contested and that the certificate or duplicate abstract and declaration are not valid until the election contest is resolved.
Iowa Code § 57.2