Online game maker Zynga Inc. reported a net loss for the last three months of 2011, weighed down by hefty stock-compensation expenses and other costs in its first quarter as a public company.

Its adjusted earnings and revenue inched past Wall Street's expectations, but that wasn't enough to lift the stock of the company that is behind the most popular games played on Facebook. Zynga's stock fell 6 percent in after-hours trading following its report.

San Francisco-based Zynga said Tuesday that it lost $435 million, or $1.22 per share, in the fourth quarter. That's down from earnings of $16.1 million, or 5 cents per share, a year earlier when it was still privately held.

Adjusted earnings were 5 cents per share in the latest quarter, surpassing Wall Street's expectations by 2 cents. This figure excludes one-time items, including $510 million in stock-compensation expenses triggered by Zynga's initial public offering of stock in mid-December.

Revenue rose 59 percent from a year earlier to $311 million as Zynga grew its user base, ad revenue and the money it makes from games such as "CityVille," "FarmVille and "Zynga Poker." On average, analysts surveyed by FactSet were expecting $302 million.

Investors may have been hoping for more. Zynga's revenue climbed just 1 percent, compared with the third quarter. In contrast, its revenue grew by double-digit percentages from one quarter to the next for the year's first three quarters.

Zynga's IPO raised $1 billion, at the time the largest IPO by a U.S. Internet company since Google's in 2004. Facebook, though, is expected to dwarf both when it goes public in the next few months. The world's largest online social network plans to raise $5 billion in an IPO that could value the company at $100 billion. In comparison, Zynga's market capitalization was about $10 billion as of Tuesday.

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