Beyonce's fans think she is pregnant with fourth child as she appears to have bump during world tour

Beyonce and Jay-Z perform together during their On the Run II tour at Hampden Park in Glasgow, Scotland. Photo / Getty Images

She recently embarked on a massive world tour with her husband.

But Beyonce fans have been quick to notice that the pop star may be hiding a growing baby bump while performing on stage during the first few shows of her On the Run II tour with Jay Z.

The Daily Mail reports that fans took to social media in speculation their Queen Bey is pregnant, with various photos and videos to back up their claims, while sources at Star magazine revealed the Crazy In Love songstress is "over the moon" with her pregnancy news.

One reason the Halo singer may have so many outfit changes on the tour is simply to conceal her growing belly and keep fans guessing. Photo / Getty Images

Fans were quick to take note of Beyonce's wardrobe choices during her recent European stops on the tour, which the couple has slated for 48 performances around the world.

"Beyonce looks pregnant again. Ya'll know they love 4's and she has all those coats for the tour," one fan wrote on Twitter.

Another fan was more than impressed with Beyonce's drive to perform for her fans even with pregnancy rumors swirling.

"Beyonce doing a worldwide tour whilst she's pregnant has got to be the biggest motivation in the world," another user commented.

Showing off what appeared to be a baby bump, a Twitter follower is convinced the star was hiding something underneath a long sparkling coat.

"But beyonce is DEFO pregnant," the user wrote with fans quick to like and retweet the images on social media.

A source at Star magazine revealed that while the news is a bit of a surprise for the couple, they're happy to welcome a new member into the family.

"It's a shock so soon after the birth of the twins, but she's over the moon," an insider revealed to the publication.

Beyonce looks pregnant again. Y’all know they love 4’s and she has all those coats for the tour

— The Purest ☯️🍀🌻🦋✨🎶🎵 (@BombshellBandit) June 11, 2018

One reason the Halo singer may have so many outfit changes on the tour is simply to conceal her growing belly and keep fans guessing.

"She's rushing to change her costumes so that she can keep the bump covered up for as long as possible," a source said. "Only a few have been entrusted with the news, but it doesn't take a genius to figure out what's going on."

While the couple may be adding another baby into the mix, the proud parents are likely celebrating their twins Rumi and Sir today as they turn one. They also have a six-year-old daughter, Blue Ivy.