* Investors hope to learn how long Fed bond-buying might continue
* Private-sector employment below expectations, inflation muted
* GM profit leaps on strong U.S. demand
* Indexes off: Dow 0.14 pct, S&P 0.22 pct, Nasdaq 0.28 pct
By Chuck Mikolajczak
NEW YORK, Oct 30 (Reuters) - U.S. stocks edged lower on Wednesday, following a string of four sessions of gains and before the release of the Federal Reserve's statement on the economy and its ultra-loose money policy.
The U.S. central bank, which will announce its decision at 2:00 p.m. (1800 GMT), is expected to keep intact its program of buying $85 billion of Treasuries and mortgage securities a month. It may indicate that its aggressive stimulus policy, which is aimed at invigorating the economy, will be extended into 2014. Several key economic indicators have shown weakness.
Many analysts expect a delay until at least March in easing the stimulus measures, which have encouraged investors to buy riskier assets, like stocks. The Dow and S&P 500 index climbed to record highs on Tuesday, the latest in a series of all-time highs.
"It's wait to see what the Fed has to say. I don't think anybody expects any surprise coming out of the Federal Reserve's meeting," said Hugh Johnson, chief investment officer of Hugh Johnson Advisors LLC in Albany, New York.
"Everybody is just stepping back to make sure."
The central bank has held interest rates near zero since late 2008 and has quadrupled the size of its balance sheet to more than $3.7 trillion through three rounds of bond buying. The purchases have made a major contribution to the S&P 500's gain of nearly 24 percent this year.
Data on Wednesday showed private-sector employers hired the fewest workers in six months in October while the consumer price index showed benign inflation, both arguments supporting the Fed's stimulus policy.
The Dow Jones industrial average fell 21.33 points or 0.14 percent, to 15,659.02, the S&P 500 lost 3.92 points or 0.22 percent, to 1,768.03 and the Nasdaq Composite dropped 10.971 points or 0.28 percent, to 3,941.367.
In the latest batch of corporate earnings, shares of General Motors Co rose 3 percent to $37.14 after the No. 1 U.S. automaker reported stronger-than-expected quarterly profit due to strength in its core North American market and a smaller-than-anticipated loss in Europe.
Shares of Yelp Inc dropped 5.6 percent to $64.99 a day after the business-search service firm reported a wider third-quarter loss.
Western Union shares slumped 12.3 percent to $16.88 after the world's largest money-transfer company reported a 20 percent drop in third-quarter profit, hurt by lower revenue from its consumer business and higher expenses.
Companies expected to report earnings after the close on Wednesday include Visa, Starbucks, MetLife and Kraft.
According to Thomson Reuters data, of the 313 companies in the S&P 500 that have reported earnings through Wednesday morning, 68.4 percent have topped Wall Street expectations, above both the 63 percent beat rate since 1994 and the 66 percent rate for the past four quarters.
Revenue's performance has been mixed, however, with 53.7 percent of S&P 500 companies beating expectations, well below the 61 percent average since 2002 but slightly above the 49 percent rate for the last four quarters.