US STOCKS-Wall St advances as Yellen keeps Fed policy intact

* Yellen, new Fed chair, takes hot seat at Capitol

* Yellen says labor market recovery far from complete

* Sprint (Frankfurt: 2S7.F - news) , CVS climb after results

* Indexes up: Dow 0.53 pct, S&P 0.43 pct, Nasdaq 0.45 pct

By Chuck Mikolajczak

NEW YORK (Frankfurt: HX6.F - news) , Feb 11 (Reuters) - U.S. stocks rose on Tuesday after new Federal Reserve Chair Janet Yellen reinforced the central bank's plan to trim its market-friendly stimulus while noting the health of the labor market needed to improve.

In her first public comments as Fed chief, Yellen, giving a balanced testimony to a House committee, acknowledged recent volatility in global financial markets but said it did "not pose a substantial risk to the U.S. economic outlook," and that she strongly supported the policy approach of her predecessor, Ben Bernanke.

Yellen's appearance before the House Financial Services Committee began at 10 a.m. (1500 GMT).

"We didn't see anything, at least in the written release that would cause us any concerns," said Paul Mangus, head of equity research and strategy at Wells Fargo Private Bank in Charlotte, North Carolina.

"Naturally the testimony is just beginning so that will be very interesting to watch, the written testimony was in many ways a continuation of what the Bernanke policies had been."

The Dow Jones industrial average rose 83.69 points or 0.53 percent, to 15,885.48, the S&P 500 gained 7.74 points or 0.43 percent, to 1,807.58 and the Nasdaq Composite added 18.85 points or 0.45 percent, to 4,167.023.

The central bank has cut its bond-buying program by $10 billion at each of its last two meetings, reducing the monthly purchases to $65 billion.

Stocks also saw a potential headwind removed when Republican leaders in the U.S. House of Representatives caved in to demands by President Barack Obama and agreed to advance legislation raising Washington's borrowing authority.

Sprint Corp, the No. 3 U.S. mobile provider, reported quarterly revenue ahead of analysts' expectations and said it added wireless subscribers in the fourth quarter. The stock was up 5.3 percent to $8.10.

CVS Caremark Corp posted higher quarterly profit as it processed more prescriptions and benefited from the introduction of new generic drugs. The stock rose 2.2 percent to $68.40.

Of 345 companies in the S&P 500 that have reported earnings through Monday morning, 67.8 percent have beaten profit expectations, above the long-term average of 63 percent, according to Thomson Reuters (Frankfurt: TOC.F - news) data. Almost 66 percent have topped revenue forecasts, above the historical average of 61 percent.

Conagra Foods (NYSE: CAG - news) lost 7.6 percent to $28.68 as one of the worst performers on the S&P 500. The maker of Chef Boyardee pastas and Slim Jim beef jerky cut its full-year profit outlook, citing weaker profits in its private label business and lower sales of certain consumer foods brands.

Infloblox Inc plunged 48 percent to $17.22 after the network equipment maker estimated second-quarter revenue below analysts' average forecast.

Cadence Pharmaceuticals Inc (NasdaqGS: CADX - news) surged 26.2 percent to $13.97 after the company agreed to be acquired by specialty pharmaceuticals company Mallinckrodt Plc (NYSE: MNK - news) said for about $1.3 billion. Mallinckrodt climbed 11.3 percent to $66.01.