What is apparently intended to be a great gag gift has been used by some woman to convince their boyfriends they are having a child.

From bogus baby bumps to ultrasounds and hospital records, FakeABaby.com sells everything one needs to fool someone into thinking they’re pregnant. They say they are gag gifts, but for some, it's no laughing matter.

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One woman, who asked to be indentified by her first name, Danielle, admits she used materials from FakeaBaby.com to convince her boyfriend she was pregnant in an effort to save their relationship.

“I faked my baby," Danielle told Inside Edition's Chief Investigative Correspondent Lisa Guerrero. "I faked a pregnancy."

Danielle’s boyfriend, Mark, took the bait.

"There was a document from a local hospital stating she's pregnant," Mark said.

The website’s sonograms and paperwork all say "for entertainment purposes only," but Danielle showed Inside Edition how easy it is to cut off the label.

“I knew that if I told him the truth that he'd probably walk away and I didn’t want to lose him,” she said, fighting tears.

Mark is not alone. Inside Edition found other men that say they been fooled.

Eric Nevel of State College, Pennsylvania, said his ex-girlfriend used a sonogram and documents from FakeABaby.com to con him into proposing. He said that he even spent thousands of dollars to lease a new house big enough for the "three" of them.

"I was very convinced she was pregnant," he told Inside Edition. "She played me like a fiddle."

Her lie finally came crashing down when Nevel says he discovered an email from FakeABaby.com on her computer, he said.

Dr. Rebecca Brightman, a Manhattan OBGYN said the ultrasounds and documents provided by the site look very convincing to the untrained eye.

“I don't think it's funny," she said. "It's really scary. The more I delved into this myself, the more I realized how this is really set up for abuse."

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And there are others who are trying to pull a profit on fake pregnancies.

While it's not illegal, Inside Edition found dozens of ads on Craigslist from expecting women offering their positive pregnancy tests — for a price.

One Craigslist ad reads: “Whether you are using it for your own amusement or to blackmail the CEO of wherever who you are having an affair with, I don’t care at all. This is a no questions asked type of deal.”

Guerrero responded to the ad and met up with a pregnant woman selling her two positive pregnancy tests for $50.

“Basically as you called me I peed in a bottle and ran to the store,” the woman said.

Guerrero then revealed to the surprised seller that she is with Inside Edition.

"Some people would say it’s unethical," Guerrero told the woman.

“I one hundred percent agree with that,” she replied.

Despite the infant fakery, Mark and Danielle are now back together and trying to keep what happened from ruining their very real lives.

So if you’re thinking of faking a pregnancy, Danielle says, “Don’t do it. “Ever, ever, ever, ever!”

FakeABaby.com did not return multiple requests for comment by Inside Edition.

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