By Martinne Geller

NEW YORK (Reuters) - U.S. apparel maker Warnaco Group Inc (WRC.N) reported higher-than-expected quarterly revenue and profit, but forecast 2010 earnings that could fall short of Wall Street estimates as it expands its retail and international businesses.

The maker of Calvin Klein underwear reported fourth-quarter net income of $11 million, or 23 cents per share, helped by its Calvin Klein sportswear and Speedo swimsuit brands. A year earlier it posted a net loss of $16.3 million, or 35 cents per share.

Excluding items, Warnaco earned 64 cents per share, topping analysts' average estimate of 57 cents per share, according to Thomson Reuters I/B/E/S.

Revenue in the fourth quarter was $505.4 million, up 14 percent and ahead of analysts' forecast of $483.97 million. The company cited particular strength in Latin America.

Warnaco said it expects to earn $3.10 to $3.20 per share in 2010 on net revenue expected to grow 5 percent to 7 percent from $2.02 billion in 2009.

Analysts on average were expecting earnings of $3.20 per share on revenue of $2.13 billion, according to Thomson Reuters

I/B/E/S.

For 2010, same-store sales are expected to rise in the low single digits on a percentage basis, the company said.

"Given some of the uncertainty from the foreign exchange markets and still tough domestic markets, we believe it makes sense for management to be conservative," said Brean Murray Carret analyst Eric Beder.

He added that Warnaco's steps to aggressively expand and increase marketing dollars should pay off if the consumer spending rebounds.

Warnaco said selling, general and administrative expenses would increase more than $70 million for 2010 from last year.

The company is aiming to expand its business by opening more retail stores and growing abroad. It said on a conference call with analysts that it planned to increase retail square footage by about 20 percent this year and take direct control of its businesses in Singapore and south China.

At the end of last year, the company operated 1,097 stores, with another 624 stores run by third parties.

Same-store sales in Warnaco's retail segment rose 4 percent during the quarter.

Within Warnaco's sportswear segment, Calvin Klein revenue rose 22 percent, offsetting a 4 percent decline for Chaps. Revenue rose 10 percent in the company's underwear and swimwear units.

The company said its gross margin increased 160 basis points to 44 percent of net revenue, while selling, general and administrative expenses represented 34 percent of net revenue, a decrease of 360 basis points.

Shares in Warnaco were slightly lower after hours after closing at $42.97, up 3 percent, on the New York Stock Exchange.

(Additional reporting by Alexandria Sage; Editing by Gunna Dickson and Steve Orlofsky)