US STOCKS-Wall St lower amid weak earnings and GDP data

* Second-qtr GDP rises 2.3 pct vs 2.6 pct est

* Facebook (NasdaqGS: FB - news) 's fall weighs on S&P, Nasdaq

* P&G slips after 6th straight sales decline; weighs on Dow

* Skechers, Mondelez jump after profits beat expectations

* Indexes down: Dow 0.37 pct, S&P 0.41 pct, Nasdaq 0.45 pct (Adds details, changes comment, updates prices)

By Tanya Agrawal

July 30 (Reuters) - U.S. stocks fell in late morning trading on Thursday as earnings from Facebook and Procter & Gamble disappointed investors and data showed that the economy expanded at a slower-than-expected pace in the second quarter.

Procter & Gamble's 3.7 percent fall dragged down the Dow, after the company reported its sixth straight quarter of lower sales.

Facebook shares fell 3.9 percent after the social media company's profit decreased, and weighed heavily on the S&P 500 and Nasdaq.

Gross domestic product expanded at a 2.3 percent annual rate in the second quarter, below the 2.6 percent rise economists had expected, even as the Federal Reserve left doors open for a possible rate hike in September.

The Fed has maintained near-zero interest rates for nearly a decade, saying it will raise rates only when it sees a sustained recovery in the economy.

"Earnings haven't been great and there is much more slack in the economy than the market or the Fed thought while big concerns such as oil and China continue to persist," said John Canally, investment strategist at LPL Financial (NasdaqGS: LPLA - news) .

"We are in a slow-growth environment and anything that knocks that down further is not a plus for the market."

The U.S. dollar continued to strengthen and was up 0.68 percent near a weekly high of $97.63 against a basket of currencies as the Fed readies to raise rates this year.

U.S. stocks closed stronger on Wednesday after the Fed statement. The S&P 500 has bounced about 2 percent higher in the past two days following a near-3 percent drop over the preceding week that had been caused in part by a rout in China's stock markets.

At 11:12 a.m. ET (1512 GMT) the Dow Jones industrial average was down 66.34 points, or 0.37 percent, at 17,685.05, the S&P 500 was down 8.72 points, or 0.41 percent, at 2,099.85 and the Nasdaq Composite was down 23.00 points, or 0.45 percent, at 5,088.73.

Seven of the 10 major S&P sectors were lower with the technology index's 0.59 percent fall leading the decliners.

More than halfway through the second-quarter earnings season, analysts expect overall earnings of S&P 500 companies to edge up 0.8 percent and revenue to decline 3.9 percent, according to Thomson Reuters (Dusseldorf: TOC.DU - news) data.

While earnings are expected to increase this quarter, valuations remain a concern. The S&P 500 is trading near 16.9 times forward 12-month earnings, above the 10-year median of 14.7 times, according to StarMine data.

Companies scheduled to report during the day include Expedia (NasdaqGS: EXPE - news) , LinkedIn and Western Union after the close.

Whole Foods Market (NasdaqGS: WFM - news) slumped 10.8 percent to $36.41 after same-store sales growth cooled.

Skechers USA (NYSE: SKX - news) jumped 14.1 percent to $146.42 as the sports shoe maker and retailer reported a better-than-expected rise in quarterly revenue.

Mondelez International (Xetra: A1J4U0 - news) rose 4.5 percent to $45.07 after reporting results that beat expectations.

Declining issues outnumbered advancers on the NYSE by 1,628 to 1,187. On the Nasdaq, 1,463 issues fell and 1,050 advanced.

The S&P 500 index showed 15 new 52-week highs and five new lows, while the Nasdaq recorded 30 new highs and 53 new lows. (Reporting by Tanya Agrawal)