The unnamed 20-year-old from Bradford posted an advert offering to sell a four-month-old baby boy for £150,000, adding he 'comes with everything included" and "deposit needed as sick of time wasters'.
It was posted on Boxing Day under the heading 'baby for sale', but has since been removed after scores of people complained. Police were contacted and the woman was tracked down and her two boys were removed from her care by social workers.
Detective Inspector Vanessa Smith told the Bradford Telegraph and Argus: "We are aware of this matter and the child concerned, who is both fit and well, is now being looked after in conjunction with relatives and social services.
"The mother is receiving appropriate care and support at this time."
While no criminal charges are expected, local children's services councillor Ralph Berry said: "It is shocking to hear about, but the priority has to be the welfare of the child, that's what the law says."
The woman, a single mother, told the Daily Mail how a 'silly, silly joke' had led to police officers coming to her house to take away her children.
She said: "I had been joking with my ex about selling sperm and eggs and he sort of dared me to put up a baby for sale – but I didn't mean our children.
"I put on Gumtree that I was selling a baby for £150,000. I just plucked that number out of thin air and I claimed I was acting as an agent for a friend.
"It was very stupid and I shouldn't have done it, but I didn't think it would be taken seriously.
"I love my boys and they make me so happy and I want them to be happy. It was just a silly, silly joke."
Gumtree said the advert had been taken down on the same day it was posted.
A spokesperson said: "We take that sort of activity extremely seriously. The most important thing is the safety of our users.
"There is nothing we can do to stop things being posted. It is an open platform and anyone can post anything, but these sorts of ads are definitely not allowed and we take action straight away."
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