Mercy, one of the largest health systems in St. Louis region and in the U.S., says it has teamed up with health insurance plan Centivo as its contract with Anthem Blue Cross is set to expire at the end of the year. Centivo will offer a health insurance plan to employers and employees in the city of St. Louis and St. Louis, Jefferson, Franklin and Lincoln counties, with coverage at Mercy facilities throughout Missouri with hopes to eventually expand across Mercy's four-state footprint.