CHAPEL HILL -- New research from the University of North Carolina at Chapel Hill ties low levels of a hormone secreted by the uterus and embryos to problems with pregnancy and fetal development.
The findings also suggest that the hormone, adrenomedullin, plays a key role in maternal susceptibility to preeclampsia, a serious pregnancy complication that occurs in the third trimester. Preeclampsia affects roughly one in fifteen pregnant women and is the leading cause of death among expectant mothers.
The UNC researchers demonstrated that pregnant mice with low adrenomedullin levels had reduced litter sizes, and while embryos implanted normally in the uterus, their spacing was overcrowded and resulted in poor growth. Because the low hormone levels were caused by a genetic mutation affecting adrenomedullin production, similar genetic changes could be linked to problems in human pregnancy, the researchers said.
"Our study provides the first genetic evidence to suggest that a modest reduction in human adrenomedullin expression during pregnancy may cause profound defects during pregnancy," said Dr. Kathleen M. Caron, senior study author and an assistant professor in the departments of cell and molecular physiology and genetics at the UNC School of Medicine.
Among the potential problems are poor implantation of the embryo, failure of the placenta to establish blood flow between mother and fetus and restricted fetal growth, Caron said. "The clinical implications are that women who have mutations in the gene responsible for expressing adrenomedullin might have greater susceptibility to these pregnancy problems, including preeclampsia."
The study was published online Sept. 14 in the Journal of Clinical Investigation and will appear in the Oct. 2 print edition.
Discovered in 1993, adrenomedullin is a powerful blood vessel dilator that is essential for life. Secreted by cells throughout the body, it is involved in m
Contact: L. H. Lang
University of North Carolina School of Medicine