Time Inc. parent Time Warner today reported that total adjusted operating income jumped 37 percent to $1.4 billion through the first three months of 2010—what it says is its highest quarterly profit in company history. Revenues for the period, meanwhile, were up five percent to $6.3 billion, marking the company’s highest revenue growth since the second quarter of 2008.

Time Inc. reported an operating income of $50 million during the first quarter versus a loss of $32 million during the same period last year. Revenues declined 1 percent to $799 million.

The division saw advertising revenues jump 5 percent and subscription revenue increase 2 percent during the first quarter. Citing Publishers Information Bureau data, Time Inc. says it increased its share of overall domestic magazine advertising 2.5 percentage points to 21.2 percent from last year’s first quarter. “The growth in advertising revenues reflected higher domestic print magazine and online revenues,” the company says. “Subscription revenues benefited from the favorable impact of foreign exchange rates at IPC, offset in part by a modest decrease in domestic magazine subscription revenues.”

Time Warner’s networks division (Turner Broadcasting and HBO) reported an operating income of $1.2 billion, an increase of 22 percent over the same period last year. Filmed entertainment (Warner Bros.) saw its operating income spike 43 percent to $307 million.

Time Warner reported $68 million in restructuring charges over the first three months of 2010, compared to $77 million during the same period last year. As of March 31, Time Warner’s net debt was $11.5 billion, unchanged from the end of 2009, due mainly to share repurchases, investment and acquisition spending, as well as dividends, the company says.