The social media company beat on both the top and bottom lines in the first quarter, and shares opened 2.9 percent up at $31.35 after trading as high as $34 in extended hours.
The stock gave up all its gains, falling below $30, after the company softened its forecast on an earnings call Wednesday morning.
The World Cup, which will be held June 14 to July 15 in Russia, will be a large advertising event in the first half of the year for Twitter, CEO Jack Dorsey said in a call with analysts.
However the company will face tougher competition in the second half the year, as it is still working through the "business recovery" it began in the third quarter of 2017, Dorsey said. The company still expects to be profitable for 2018.
He advised that revenue may mimic 2016, but urged analysts to base their revenue models on Twitter's sequential revenue growth.
"As we look ahead to the remainder of the year, we remain optimistic about our ability to execute on our priorities and deliver value for advertisers on our platform," Twitter wrote in a letter to shareholders. "However, we face increasingly difficult comparables in the second half of 2018 as we approach the anniversary of the broad-based recovery that began in the second half of 2017."
The stock is up more than 30 percent on the year and more than 110 percent in the 12-month period.