Kelly Donegan of Buckinghamshire looked down at her bump to see the pin poking out, only inches away from her unborn baby, Metro reports.
The 26-year-old had been feeling some discomfort for a while and had also noticed a bump under her skin where the pin must have been. The pin is thought to be from an operation in 2009 to remove Kelly's appendix.
Kelly was reassured by her doctor that the pain was nothing to worry about but the pin popped out just six weeks before the birth.
However, the pin remains sticking out of her bump and Kelly must wait until the end of her pregnancy until surgeons can remove it for safety reasons.
She said: "They can't even do an X-ray to see how much of the thing is inside me because X-rays are dangerous for pregnant women."
Professionals have reassured Kelly that her baby will remain unharmed but have told her that she may need an operation to remove the pin after the baby is born. Until then the pin can only be trimmed of the sharp end so that it doesn't catch on things.
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