A research team at the University of Calgary has pinpointed a hormone in pregnant women that appears to repair the damage created by multiple sclerosis.

The results of the Calgary study are being published in Wednesday's issue of the Journal of Neuroscience.

The chronic disease known as MS causes the body's own immune system to attack myelin, a fatty substance that coats the brain and spinal cord.

As a result, lesions develop, making it difficult for messages to travel through the central nervous system, and eventually leading to a loss of sensation and movement.

But there is evidence that MS goes into remission during pregnancy, and in some cases the body actually begins to repair the damage.

The Calgary team has determined that a hormone called prolactin which is produced in pregnant women may be responsible for the changes in pregnant women with MS.

The researchers treated mice that had damaged myelin with prolactin, and observed that damage to the spinal cords was repaired, said Dr. Samuel Weiss, the senior author of the study and director of the Hotchkiss Brain Institute.

"If you put it all together, it suggests that increases in prolactin makes more myelin, which may contribute to some of the repair that is seen during pregnancy in MS," explained Weiss.

"It also suggests that prolactin itself may be a potential therapeutic model for treating MS."

Dianne Rogers, 37, has hope that the results will lead to a breakthrough. She was diagnosed with MS when she was 25, and experienced a significant improvement while she was pregnant. Her eyesight, damaged by MS, improved dramatically.

"It was like a birthday present and a Christmas present all rolled in together. It was like, wow, something I don't have to worry about or think about."

However, after the pregnancy the symptoms returned, and the disease, which had been in relapse prior to the pregnancy, seemed to pick up steam after her child was born. Her vision again began to fail and she experienced a loss of sensation in her left side.

"A month and a bit after, I ended up in a severe relapse. As soon as those pregnancy hormones were gone, slam -- I was right into it again."

An official with the Multiple Sclerosis Society of Canada said the announcement is a significant development in the effort to battle the disease.

"We're looking at a naturally occurring hormone that has never been looked at on how it can improve MS symptoms," said Stewart Wong.

"People who have MS today should be pleased with the research that's taking place."

Other current treatments attempt to halt or slow down the progression, but the experimental procedure could be the first to actually repair damage done by MS.

"This is a new direction in the treatment of MS. Rather than controlling the disease process...we want to allow recovery from the disease process," Weiss said.

Human trials could begin within five years, he said.

However, experts are cautioning that the research is still in its infancy. And the new results only represent a possible treatment, not a cure.

Other current treatment options target the immune system in its early stages, but there are no treatment options for after lesions form on the brain and spinal cord.

With a report from CTV Calgary and files from The Canadian Press