Even if Halloween is not your thing, who doesn't love a good scare? And according to science, evolution favours screamers.

The theory goes that the genes of pre-historic humans with a lesser ability to differentiate between screams relating to an emergency, have all but died out, and we are "the descendants of individuals who were good screamers."

But, as this mom-to-be found, not all frights are made equal.

Curious about her baby's gender, Iyanna Carrington from Virginia, US got much more than she bargained when her 24 week 3D scan went from pleasant to spooky.

One minute she was told everything was normal and the next, a weird glitch turned her fetus into, well, a devil baby.

"They showed her face and she looked normal. Then the nurse confirmed she was girl, but I knew that deep down already. Then they put it back on her face and she was just looking right at me like that," she told the Daily Mail.

Although Halloween is often associated with frightening costumes and scary pranks it can also be a fun time to do other not-so-scary activities.

Reassured by her doctors that the freaky image was nothing out of the ordinary, Carrington said that both herself and the father of her baby had a good laugh over everything.

"We were just laughing at the scan. You can see her little nose on [the other image]. You can tell she's beautiful really."

At least the mom now has a cool story to tell her baby girl when she's all grown up.