Washington, Sep 16 (IANS): A US woman has undergone a surgery after removing and swallowing her engagement ring in her sleep due to a nightmare in which she and her fiancé were on a speeding train and she was forced to swallow the ring to protect it from "bad guys".

Jenna Evans, 29, woke at her home in California to realize the episode had been a dream, but saw her diamond ring was missing. The woman said she woke up her fiancé to explain, and the couple went to a hospital.

The incident took place late last week. Evans said she struggled to recall the situation to medics "because I was laughing/crying so hard".

An X-ray scan identified the 2.4-carat ring in her stomach and doctors agreed it would be unwise "to let nature take its course", media reports said.

Evans later had a procedure to remove the ring but said she was asked to sign release forms in case of her death. "Then I cried a lot because I would be so mad if I died. I waited a long time for that damn engagement ring."

The surgery was a success and Evans said she woke up "hysterically crying".