Baidu.com's (BIDU) shares fell as much as 8.5 percent in early trade on Wednesday, the day after China's largest Web search engine reported earnings for the first time as a public company.

While the company's report showed a sharp rise in earnings and revenue for the second quarter, the numbers raised questions about a possible slowdown in revenue growth in the current third quarter.

Thanks to higher online marketing revenue, the company said overall revenue more than doubled to 69.7 million yuan, or $8.4 million, from 24.1 million yuan, That represents a 53 percent rise over revenue in the first quarter.

But according to the forecast — which calls for total revenue of 77.4 million yuan to 81.2 million yuan ($9.6 million to $10.0 million) — the sequential growth will slow considerably in the third quarter.

Based on its forecast, revenue growth from the second to third quarters would slow to just 11 percent to 16.5 percent.

Hurt by the forecast, Baidu shares were down $1.66 at $80.34 in Nasdaq trade after dipping as low as $75.

Baidu shares more than quadrupled in value in their U.S. market debut on Aug. 5 — the most spectacular entry ever by a foreign company, overshadowing world Internet search leader Google Inc.'s (GOOG) float last year.

Baidu shares finished almost 354 percent higher at $122.54 on their first day of trading, but have since retreated. The shares were first offered at $27.