In light of the balloon hoax, I'm sure, Wikipedia showcased as its featured article yesterday, the story of Mary Toft.
Accordingly, Mary Toft, way back in 1726 (1726!!), perpetrated a hoax in England that was staggering in its complexity and repulsiveness. She actually inserted dead rabbit parts into her womb following a miscarriage and claimed to give birth to them later. She followed up this particularly disgusting act with more dead rabbit parts, probably some cat and possibly a pig.
For this twisted bit of creativity, she was a nine-days-wonder in George I's England. In the intervening centuries, our understanding of human reproduction has improved greatly (thankfully!), but at that time she had doctors believing her.
Wikipedia says she was jailed briefly when the hoax was discovered, but later freed "as it was unclear as to what charge should have been made. The Toft family made no profit from the affair."
Poor Mary Toft, born 280 years too soon for reality TV.