A lot of social media users aren't finding Justin Bieber's April Fools' joke funny.

The "Love Yourself" singer, 25, took to Instagram Monday to share a caption-less picture of an ultrasound, implying that he and wife Hailey Baldwin, 22, were expecting their first child together.

Bieber took the joke a step further by sharing several pictures of Baldwin touching her bare stomach while surrounded by two gloved medical professionals, in what appeared to be a doctor's office. "If U thought it was April fools," he added.

His initial posts were filled with comments of support from friends and fans who congratulated the couple on their "miracle," while others questioned if this was just an elaborate April Fools' joke.

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Turns out, it was.

Bieber later added a third Instagram post of a puppy photoshopped into the ultrasound. "Wait omg is that a,,, APRIL FOOLS," he captioned the picture.

On Tuesday, Bieber took to social media yet again, this time to apologize for his prank-gone-wrong.

"There’s always gonna be people offended, there’s also people who don’t take jokes very well, I am a prankster and it was APRIL FOOLS. I didn’t at all mean to be insensitive to people who can’t have children," he wrote. "A lot of people I know, their first go to prank on April fools is telling their parents they are pregnant to get a big reaction. But I will apologize anyway and take responsibility and say sorry to people who were offended."

He continued, "I truly don’t want anyone to be hurt by a prank.. it’s like when I shoved cake in my little sisters face for her birthday expecting her to laugh but she cried. You sometimes just don’t know what will hurt someone’s feelings not to compare pregnancy with cake in the face but it’s just to paint the picture of not knowing what will offend. Some might have laughed but some were offended .. I think With pranks u sometimes have to roll that dice."

While some users called Bieber's prank "genius," others said pregnancy is no laughing matter, slamming the pop star for insensitivity for couples who struggle to conceive or have lost children.

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"Not funny," user britt_saddler commented under the puppy post. "As someone who has experienced many losses and 9 yrs of infertility it is hard to see April Fools pregnancy announcements. I hope you truly are expecting though because it is an amazing gift and blessing."

User maribellemf added: "I hope y'all never experience infertility or infant loss. Faking a pregnancy is nothing to joke about. This is (expletive) insensitive."

"You both should be ashamed of yourselves! Do you know how many women struggle with infertility and pregnancy loss?" user illinoisturtle commented. "This subject is not a joke and I do pray to God you both never go through infertility or pregnancy loss. Maybe you should have a little more decency and respect for others."

The backlash follows a growing number of social media users advocating for an end to fake pregnancy announcements on April Fools' Day.

"1 in 4 women miscarry. 1 in 8 couples experience infertility. 1 in 160 pregnancies end in stillbirth," Kelcie Mae tweeted ahead of April 1. "Think before you prank on April Fools Day, because pregnancy is not a joke. Don't degrade something so precious and valuable."

Ahead of the joke-filled day, Main Line Fertility reminded Twitter followers Friday that, "We love a good laugh, but pregnancy is not an April Fools Joke."

Bieber has not addressed the backlash, and all three posts remain on his Instagram page. USA TODAY reached out to his rep for comment.

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