The study was conducted by researchers at the National Institute of Child Health and Human Development (NICHD) and the National Institute of Arthritis, Musculoskeletal and Kidney Diseases. The study appeared in the October issue of The Journal of Clinical Endocrinology and Metabolism.
"This finding has important implications for understanding why immune disorders may subside during pregnancy, but flare up again after birth," Duane Alexander, M.D., director of the NICHD. "Understanding the immune processes involved may provide important new therapies for each of these conditions."
Rheumatoid arthritis (RA) is a disorder in which the immune system apparently causes pain, swelling, stiffness, and loss of function in the joints. In multiple sclerosis, the immune system attacks the brain and nervous system.
The immune hormones Interleukin 12 (IL-12) and tumor necrosis factor alpha TNF alpha hormones are involved in triggering the body's immune cells to ward off disease causing invaders, explained the study's senior investigator, George P. Chrousos, M.D., Chief of NICHD's Pediatric and Reproductive Endocrinology Branch. Both hormones also seem to be involved in the swelling and tissue destruction seen in rhematoid arthritis and multiple sclerosis. Similarly people with these conditions also have higher-than-normal amounts of the two immune hormones.
In pregnant women who have either multiple sclerosis or rheumatoid arthritis, symptoms may ease up or even disappear during the third trimester of pregnancy, Dr. Chrousos said. After the women give birth, however, their symptoms often return. Similarly, pregnant women who do not have either disorder may develop one of them within a year of
Contact: Bob Bock
NIH/National Institute of Child Health and Human Development