DENVER -- It's been 4 1/2 years since Gabrielle Schmidt was diagnosed with breast cancer. Since then, she has undergone 18 months of chemotherapy and two surgeries. Now, Schmidt is facing another challenge: not being able to sleep.

"You get to a point because you're so exhausted that you kind of just sit and become a zombie because you're so very tired," said Schmidt.

On an average night, she would wake up four or five times. She's not alone.

"There's probably two times the amount of insomnia in women who've had breast cancer, and it can happen the minute you even think you have breast cancer all the way through treatment," said Dr. Ellyn Matthews from the University of Colorado Denver College of Nursing.

UC Denver College of Nursing started a sleep study last year to see if cognitive behavior changes could help breast cancer patients suffering from insomnia. Schmidt enrolled in the study about eight months ago because insomnia was taking a toll on her life.

"It affects your memory and just your way of life and quality of life because you're so stressed out. You need to be able to relax, relax and let your body and mind rest," said Schmidt.

Schmidt now has a set bedtime and wake-up time. She does not have a clock in her bedroom. She also listens to soothing music to help relax her before bedtime. So far, they behavioral changes appear to be working.

"I can't believe the difference in my energy levels and I'm not as tired as I used to be, which is great," said Schmidt.

Dr. Matthews is currently looking for more breast cancer patients to enroll in this sleep study. For more information you can go to www.uccc.info