Aetna reported higher-than-expected quarterly revenue and earnings on Tuesday as membership grew in its government business, under which it sells Medicare and Medicaid plans.
Shares of Aetna were up 1.6 percent at $116.28 in morning trading.
The insurer affirmed its full-year outlook for operating earnings of $7.90 to $8.10 a share.
Aetna's medical benefit ratio, the percentage of premiums spent on claims, rose to 82.4 percent from 81.1 percent a year earlier as medical costs increased in the Obamacare business.