McDonald's Corp reported a lower-than-expected rise in worldwide August sales at established restaurants on a steep drop in Japan and a lull in new product launches in the United States.

The world's largest hamburger chain, whose shares fell 4.4 percent on Friday, said sales at restaurants open at least 13 months rose 3.5 percent globally. Analysts polled by Thomson Reuters were looking for an increase of 4.3 percent.

Same-restaurant sales rose 3.9 percent in the United States, just shy of analysts' 4.0 percent expectation. In Europe -- McDonald's largest market -- the company reported an increase of 2.7 percent, missing analysts' estimate of a 4.7 percent increase.

To help increase sales, McDonald's has relied on new products like breakfast oatmeal and a beverage overhaul that has included the introduction of fruit smoothies and other drinks.

In August 2010, demand for smoothies helped drive up U.S. same-restaurant sales by 4.6 percent.

This year new product launches were really weighted toward the front half of the summer, Morningstar analyst R.J. Hottovy said.

But he noted the company was still doing better than its competitors in terms of same-restaurant sales.

It's still comping positive while a lot of their competitors are still squarely in negative territory, Hottovy said.

McDonald's sales and profits for months have been the envy of the global fast-food industry, which means that the company is punished when results meet or miss expectations.

The company has been outpacing rivals like Wendy's Co , Burger King Corp and Yum Brands Inc's KFC by attracting a broader range of diners than fast-food's typical young adult males.

WEAK JAPAN WEIGHS

McDonald's reported a 0.3 percent decline in Asia/Pacific, Middle East and Africa, while Wall Street had forecast a rise of 3.5 percent.

Asia was dragged down by a sharp decline in comparable sales in Japan, where consumers are still adjusting to the aftermath of the March earthquake and tsunami.

Janna Sampson, co-chief investment officer at Oakbrook Investments, said the weak results in Japan were troubling, given how many months have passed since the earthquake and tsunami struck in March.

I would have thought that was already priced into expectations, Sampson said. But one month does not make for a pattern ... If we see that continue in September, it becomes more problematic.

Earlier this week, Red Lobster and Olive Garden parent Darden Restaurants Inc warned that Hurricane Irene had dented its quarterly earnings by 2 cents per share.

But Irene had only minimal impact on McDonald's sales, a company spokeswoman said.

Oak Brook, Illinois-based McDonald's shares were down 4.4 percent at $84.71 in New York Stock Exchange trading.

(Additional reporting Lisa Baertlein in Los Angeles; Editing by Lisa Von Ahn, Dave Zimmerman)

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