(Reuters) - Expedia Inc <EXPE.O> reported lower-than-expected quarterly revenue due to higher promotions for its member loyalty program and discounts to promote new hotel listings, sending the company's shares down more than 6 percent in extended trading.

Expedia, which owns a majority stake in Trivago, and the founders of the travel website have agreed to explore the feasibility of taking the business public, Expedia said.

The world's largest online travel services company said its bookings in the latest quarter slowed due to the acquisition of rival Orbitz Worldwide Inc, "self-inflicted" wounds such as technology upgrades and the recent spate of attacks in Europe.

"Travel demand to France is a particular challenge. With each subsequent event we have seen a worsening of the trend," Chief Financial Officer Mark Okerstrom told Reuters.

However, bookings out of the United States into London accelerated once the pound fell against the dollar following Britain's vote on June 23 to leave the European Union, he said.

The higher promotions and discounts by Expedia led to a 5 percent drop in revenue per room night in the second quarter ended June 30.

The company, which owns Expedia.com, Hotels.com, Hotwire and other brands, said it expects revenue per room night to decrease through 2016.

Hotel room night bookings rose 20 percent in the quarter, excluding eLong, a Chinese travel website it sold in May 2015. But, the growth was slower than the 35 percent increase a year earlier.

Even the 25 percent rise to $18.86 billion in gross bookings on Expedia sites, excluding eLong, was the slowest in three quarters.

Expedia said it expects organic hotel room night bookings to improve later this year, but cautioned that a continued slowdown would mean full-year EBITDA would be at the lower end of its forecast.

The Bellevue, Washington-based company expects EBITDA (earnings before interest taxes, depreciation and amortization) to grow 35-45 percent this year.

Second-quarter revenue rose to $2.20 billion from $1.66 billion, but fell slightly short of analysts average estimate of $2.25 billion, according to Thomson Reuters I/B/E/S.

Net income attributable to Expedia fell to $31.6 million, or 21 cents per share, from $449.6 million, or $3.38 per share, a year earlier, when it recorded a $395 million after-tax gain on the sale of eLong.

Excluding items, its earning of 83 cents per share beat analysts' estimates of 78 cents.

Expedia's shares were trading down 6.4 percent at $11.69 after the bell.

(Reporting by Arunima Banerjee in Bengaluru; Editing by Don Sebastian and Savio D'Souza)