Pinterest (PINS -1.41%) stock plunged by more than 10% in after-hours trading following the release of its first-quarter earnings report. While it reported stellar numbers for the first quarter, worries over how Pinterest will perform amid reopenings left traders selling shares of the San Francisco-based media giant.

Woman sips coffee as she uses her laptop while lounging on her couch.

Image source: Getty Images.

On the surface, the sell-off seems to make little sense. First-quarter revenue grew 78% from year-ago levels to more than $485 million. It also cut its net loss significantly, reporting negative earnings of $22 million. Pinterest lost about $141 million in the first quarter of 2020.

Moreover, the number of monthly active users (MAUs) rose by 30%, boosted by massive growth in the company's non-U.S. user base. Additionally, these users drove increased revenue as the average revenue per user (ARPU) surged by 34%.

However, the selling occurred as the company warned growth might take a breather as the economy reopens. Other peers and industry watchers expect online growth to slow as users return to offline activities. This likely explains why Pinterest only offered guidance for the upcoming quarter.

Still, Pinterest stock may appear priced for perfection. It has retreated in recent weeks and pulled back after almost reaching the $90 per share level. Though the sell-off takes Pinterest to about $70 per share, that still amounts to a 185% gain over the last 12 months. Moreover, it still sells for about 25 times sales.

Nonetheless, management predicted 105% revenue growth for the second quarter compared to the same quarter last year. It also expects to see percentage MAU growth in the mid-teens.

Finally, even though nobody knows how reopenings will affect user activity, the value proposition for Pinterest stock will likely not change. The company plans to continue investing in content, an improved Pinner experience, shopping, and success for advertisers.

"We think these investments will support long-term growth and continue to build the foundations for a scaled business over time," the company said in its shareholder letter.