* Facebook shares down as expenses seen rising
* Orbital Sciences falls after rocket explosion
* Dow up 0.1 pct, S&P flat, Nasdaq down 0.4 pct (Updates to midday, changes comment)
By Rodrigo Campos
NEW YORK, Oct 29 (Reuters) - U.S. stocks were little changed on Wednesday as a drop in basic materials shares offset gains in the energy sector, with traders looking ahead to a statement from the U.S. Federal Reserve as it winds down its stimulus program.
The Nasdaq Composite was pressured by a decline in Facebook shares as investors fretted over its spending plans.
DuPont, down 2 percent at $66.62, was the largest drag on the materials sector of the S&P 500 after it said there were "competitive advantages" in keeping its businesses together. Activist investor Nelson Peltz has urged DuPont to separate its various businesses in a move that has supported the company's shares.
Equities mostly held on to recent gains, with the S&P 500 up 6.6 percent in the last nine sessions as earnings have mostly been strong. So far this reporting season, 73.5 percent of S&P 500 companies have exceeded profit expectations. In a typical quarter since 1994, 63 percent of companies beat estimates, according to Thomson Reuters data.
"The trend today is company-specific," said Kim Forrest, senior equity research analyst, Fort Pitt Capital Group in Pittsburgh.
She said the takeaway from a glut of company calls is "the U.S. is the best house in an ugly neighborhood and that doesn't seem to be abating."
At 11:48 a.m. GMT (1548 GMT) the Dow Jones industrial average rose 14.51 points, or 0.09 percent, to 17,020.26, the S&P 500 gained 0.59 points, or 0.03 percent, to 1,985.64 and the Nasdaq Composite fell 19 points, or 0.42 percent, to 4,545.30.
The Fed is seen likely to announce that it will no longer add to its holdings of Treasury bonds and mortgage-backed securities after it ends a two-day policy meeting later on Wednesday, effectively ending a program that at its peak pumped $85 billion a month into the financial system.
Facebook Inc shares fell 6.1 percent to $75.84 the day after the social network announced an increase in spending in 2015 and projected a slowdown in revenue growth this quarter.
Hershey Co shares fell 3.3 percent to $92.37 after the chocolate maker cut its full-year earnings and revenue growth forecasts, citing higher dairy prices, a stronger dollar and weak sales growth in some markets.
Shares of American Realty Capital slid 35.6 percent to $7.97 after it said some of its previous financial statements were unreliable.
Orbital Sciences Corp shares fell 15.9 percent to $25.54 a day after its unmanned rocket exploded seconds after liftoff from a commercial launch pad in Virginia, marking the first accident since NASA turned to private operators to deliver cargo to the International Space Station. Orbital Sciences is in the midst of merging with Alliant Techsystems' aerospace and defense division, and its shares fell 3 percent to $125.93. (Reporting by Rodrigo Campos; Editing by Lisa Von Ahn, Nick Zieminski and Meredith Mazzilli)