They told a sinister story of how they would tell their parents the “bald men are coming” in the run up to another cosmic kidnap.
The tale was revealed by Audrey Starborn Hewins at the 26th annual International UFO Congress in Fountain Arizona.
Ms Hewins, 43, from Oxford, Maine in the United States, attended the conference which aimed to give “therapy” to “alien abductees”.
She claims to have had contact with aliens since the age of just five.
She told how her identical twin, Debbie, was also visited by grey aliens as they grew up in Athens, Ohio.
Audrey told People website: “We’d tell our parents, ‘We don’t want to go to bed — the bald men are coming’.
“They started doing all kinds of experiments on us when we were 12.”
Audrey claims she was rescued by aliens from drowning in later years.
She said: “It was then that I decided to dedicate my life to helping others who have also had encounters.
“I won’t want them to feel alone. It’s hard for people to come forward because they’re afraid that everyone will think they’re crazy.
“Only another experiencer can fully understand.”
Robert Davis, a neuroscientist from North Port, Florida, told the conference about a research project involving 2,300 alleged abductees.
He said: “Despite initial feelings of confusion and anxiety, many UFO ‘contact experiencers’ manage to reach a place of integration and healing.
“But for some it can be a difficult, long-term struggle. They often find that speaking of their experience can be traumatic to their psychological well-being and have devastating consequences. For many, it’s frightening to accept that this experience is valid.
“It’s unreasonable to think that they all would be lying or reporting dreams and fantasies.
“These events are consistently reported and should be taken seriously by everyone, in spite of their uniqueness.”
Sceptics claim there is no evidence for alien abductions, other than individual people’s accounts that are often based on dreams, and the number have increased with the rise of the internet.