It has long been common knowledge that pregnant women with multiple sclerosis (MS) experience a sharp drop in the disease's symptoms during the course of their pregnancy.
Some years back, Dr. Rhonda Voskuhl, director of UCLA's Multiple Sclerosis Program, and her colleagues discovered the cause. They found that a female sex hormone called estriol, which is produced during pregnancy, was responsible for the suppression. Four years ago, Voskuhl followed that discovery with a pilot study in which 10 non-pregnant women with MS were given estriol, yielding what she described as "pretty remarkable" results an 80 percent drop in inflammatory lesions in the brain, a hallmark of the disease.
This month, Voskuhl begins a much larger trial of estriol, one that will involve 150 patients at multiple locations over the next two years. The prospects, she said, are exciting.
Multiple sclerosis is an autoimmune disease of the central nervous system that attacks the tissue surrounding the brain's nerve fibers. This tissue, called myelin, can be thought of as the insulation wrapped around an electrical wire. When the myelin is damaged, the nerve's ability to send signals to and from the brain is interfered with, resulting in symptoms common to MS, including problems with balance, memory, vision loss and more.
Currently, anti-inflammatory drugs used to treat MS lessen the symptoms and slow the progression of the disease. But they must be given by injection daily, weekly or monthly depending on the drug and are expensive, costing between $12,000 to $24,000 a year.
Estriol is a hormone produced by the placenta that is virtually undetectable until pregnancy, when it progressively increases. It is thought that its role is to suppress a woman's immune system when she is pregnant, so that the fetus will not be seen by the body as a foreign "invader."