* Q1 adj EPS $1.01 vs est. $0.99
* Revenue rises 7.6 pct to $10.67 billion
* Says outlook for North America remains uncertain
April 19 (Reuters) - Schlumberger Ltd, the world's largest oilfield services company, reported a profit that topped analysts' estimates for the sixth straight quarter, helped by robust drilling activity outside North America.
The company, which reported a 7.6 percent rise in first-quarter revenue on Friday, said it continued to see strong and consistent growth in regions such as Saudi Arabia, Iraq, China and Australia but the outlook for North America was uncertain.
Schlumberger said there had been no improvement in dry gas drilling in North America, despite significant drawdowns on inventories.
Weak natural gas prices have made drilling for the fuel uneconomic, bringing down the prices oilfield service companies charge for services such as pressure pumping.
Schlumberger, which generated roughly two-thirds of its 2012 revenue from its international operations, is better insulated from the drilling slowdown in North America than rivals Halliburton Co and Baker Hughes Inc.
Baker Hughes, the world's third-largest oilfield services provider, reported a 30 percent fall in profit on Friday, citing weak drilling activity in North America.
Schlumberger said strong activity in Canada and solid results from the U.S. Gulf of Mexico had partially offset weakness in U.S. land drilling.
"International strength, in combination with resilience to challenging market conditions in North America, led to solid performance in the first quarter," Chief Executive Paal Kibsgaard said in a statement.
Although natural gas prices rose 15 percent in the first quarter, drilling has not bounced back as gas producers have trimmed exploration budgets for 2013.
Schlumberger warned last month that North American activity was weaker than expected in the first quarter as U.S. drillers returned to work at a slower pace than expected.
Net income fell 3.3 percent to $1.26 billion, or 94 cents per share, for the quarter ended March 31. Profit, excluding items, was $1.01 per share. Revenue rose to $10.67 billion.
Analysts had expected earnings of 99 cents per share on revenue of $10.73 billion, according to Thomson Reuters I/B/E/S.
Schlumberger shares closed at $71 on Thursday on the New York Stock Exchange.