Mo. Rev. Stat. § 104.801

Notwithstanding any law to the contrary, any legislation enacted by the general assembly which mandates the coverage of specific health benefits, services, or providers in the policies or contracts of insurers, health services corporations, health maintenance organizations, or other third-party payors, on and after January 1, 1991, also shall apply to the health benefit plans of the Missouri state employees' retirement system, the Missouri state transportation department retirement system, and any other health benefit plan provided by the state on behalf of its employees.