(REUTERS) -- Humana Inc. reported a quarterly profit that met analyst estimates, but the health insurer failed to raise its full-year forecast up to Wall Street's target and its shares fell 5.4 percent.

Shares of the large provider of Medicare plans for seniors have soared in the past year as Wall Street grows more bullish on the industry's opportunities in Medicare. After Monday's results, some investors may have been selling to lock in profits, said Les Funtleyder, a portfolio manager with Miller Tabak.

The results were good; expectations were too high, said Funtleyder.

Louisville, Kentucky-based Humana has drawn investor favor as many on Wall Street see its presence in privately run Medicare plans as a sweet spot. Its stock rose 60 percent in 2011. Insurers are expected to capitalize on the U.S. postwar baby boom population becoming eligible for Medicare, the government health program for the elderly.

Humana did nudge up its profit view for the year on Monday, as it raised its forecast for membership additions to its Medicare Advantage rolls by 40,000. It now expects to add about 190,000 individual members to such plans this year.

After soundly topping estimates earlier in 2011, health insurers' profit reports have been more tepid in the latest quarter, and some 2012 forecasts have fallen short of Wall Street targets.

Humana's quarterly net income jumped to $199 million, or $1.20 per share, from $107 million, or 63 cents per share, a year earlier.

Humana reported a relatively solid fourth quarter... although not crushing expectations as the company did during the first three quarters of the year, Leerink Swann analyst Jason Gurda said in a research note.

Earnings were in line with Wall Street's average estimate, according to Goldman Sachs analysts. Excluding a charge of 13 cents a share for a donation to its charitable fund, earnings would have been 11 percent above expectations, according to Jefferies & Co analyst David Windley.

Revenue rose 9 percent to $9.06 billion, below the $9.24 billion that analysts expected, according to Thomson Reuters I/B/E/S.

Medicare Advantage enrollment stood at 1.64 million at the end of December, up 12 percent from a year earlier. The company gained 173,000 members in January, reflecting results from the annual enrollment period for 2012.

For 2012, Humana forecast earnings of $7.50 to $7.70 per share, up from its earlier outlook of $7.40 to $7.60. Analysts have been looking for $7.99.

While management guidance raise was modest, we see this as the bullish signal we are looking for and view a bull case scenario of $9.50 EPS in 2012 as probable, Sanford Bernstein analyst Ana Gupte said in a research note.

Humana shares fell 5.4 percent to $85.28 in morning trading on the New York Stock Exchange. Through Friday they were up 3 percent this year.

(Reporting By Lewis Krauskopf; Editing by Lisa Von Ahn and John Wallace)