Facebook warns its growth is about to 'decelerate significantly' after the pandemic kept people online last year

• Facebook said growth will slow down in the coming months after a pandemic-driven boom.
• For its second quarter, however, the firm surpassed estimates and reported $29.1 billion in revenue.
• Facebook also warned of expected obstacles "from regulatory and platform changes."

Facebook on Wednesday reported its second-quarter earnings that largely exceeded investor expectations while warning of growing pains to come.

Here's a look at the key numbers:

• Revenue: $29.1 billion versus $27.9 billion expected.
• Earnings per share (EPS): $3.61 versus estimates of $3.02.
• Total monthly active users (MAUs): 2.9 billion versus estimates of 2.9 billion.

Facebook's MAU count is tied to its lucrative advertising business. The total number of ads delivered rose 6% year-over-year, Facebook said, while revenue from the segment was up 47%.

User numbers ballooned during 2020, as the pandemic kept people inside and online, but the firm said: "We expect year-over-year total revenue growth rates to decelerate significantly" in the second half of 2021.

Shares fell about 4.5% in late trading following the release.

The company hit a major milestone during its second quarter, surpassing a $1 trillion market capitalization in late June. Facebook passed that mark after a US court threw out the Federal Trade Commission antitrust lawsuit against the company, as well as one put forward by state attorneys general.

Facebook is the fifth US company to hit the $1 trillion market cap milestone.

The company's earnings come after it decided in early June that former President Donald Trump will be suspended from the platform until at least January 2023.

Facebook and its Big Tech peers also face potentially new legislation designed to keep them from growing too large and powerful. Congress unveiled the package of five antitrust bills in mid-June.

The company said it continues "to expect increased ad targeting headwinds in 2021 from regulatory and platform changes, notably the recent iOS updates." Investors were watching how a new privacy update from Apple would impact its bottom line.

The tech world is under antitrust scrutiny more broadly as lawmakers zero in on big industry players.