NEW YORK — For the past three years, the burning question for Twitter has been whether it can get more people to use its social media service.

For now, it looks like the company has stanched the loss of millions of regular visitors — although rapid user growth remains another issue entirely. But in another trouble spot, revenue growth from Twitter’s advertising business is also coming in lower than expected.

On Tuesday, Twitter said that 310 million monthly visitors used the service in the first quarter, a modest jump from the 305 million users that the company had in the last three months of 2015. The 305 million figure excluded so-called fast followers who used a text-message version of the service. The company no longer includes fast followers in its user numbers. A year earlier, Twitter posted the total users at 302 million.

Revenue, which has long been a strong part of the business, was $595 million for the first quarter, up 36 percent from $436 million a year ago. That fell short of analysts’ estimates of roughly $607 million. Twitter said marketers “did not increase spending as quickly as expected.’’

The company’s net loss was $80 million, or 12 cents a diluted share, narrower than the $162 million loss from a year earlier.

The small increase in the service’s users may not prove to be fast enough growth for investors, who regularly compare Twitter’s efforts to break into the mainstream to Facebook, the social network that has 1.6 billion users. And now there is the lower-than-expected revenue to add to the mix.

“On the one hand, it’s just a user number metric. But it gets increasingly more important because the number keeps flatlining,’’ said Mark Mahaney, an Internet analyst for RBC Capital Markets. “And it certainly says something that the company has laid this metric out as a goal, and has made many product and marketing improvements with this particular goal in mind.’’

Twitter stock plummeted more than 10 percent in after-hours trading.