Major health insurer Anthem will scale back its presence in Missouri next year and will be in just 68 of the 85 counties where it currently offers plans.

Anthem's decision comes amid ongoing worries about the number of Obamacare insurers that will offer coverage in 2018. About a week ago, the last "bare" county to not have any Obamacare insurer was filled with an insurer, but concerns still remain about whether there will be enough competition.

Anthem said in a statement it was pleased that the federal government has taken some steps to address "the long term challenges all health plans serving the individual market are facing."

The individual market is used by people that don't have an insurance plan through their job and includes Obamacare's exchanges. Anthem said it will sell plans on and off the exchange in the 68 Missouri counties.

Anthem said it has been difficult to price plans due to the "shrinking and deteriorating individual market, as well as continual changes and uncertainty in federal operations, rules and guidance."

The company has already left some Obamacare offerings in 2018, including in Virginia.

Anthem singled out as problems the restoration of a health insurer tax that was placed on a moratorium for 2017, and the lack of guidance on cost-sharing reduction subsidies to insurers. The latter payments reimburse insurers for lowering co-pays and deductibles for low-income Obamacare customers.

The White House hasn't made a decision on whether to keep the payments going in 2018, but Congress is eyeing funding the payments through a bipartisan stabilization plan.