One last insurer offering coverage on the First State's health insurance exchange

Aetna, which covers almost 12,000 Delawareans under the Affordable Care Act, is pulling out of the state's health insurance exchange.

The company informed state insurance regulators Wednesday it would not participate in Delaware's health insurance marketplace for 2018.

Officials said coverage for Aetna customers will last through the end of this year, but that anyone with a pre-existing condition for which they were being treated may be able to continue having that treatment covered.

The move leaves Highmark Blue Cross Blue Shield of Delaware, which has most of the individual market share in Delaware, as the only insurer providing coverage on the state's health insurance exchange.

Regulators last year approved average rate increases in the individual market of 32.5 percent for Highmark and about 23 percent for Aetna.

Aetna says it will also stop selling coverage in Nebraska and Delaware next year, the last two states where it remained committed.