Prematurity research

• Researchers are working to identify the causes of premature birth.
• In progress: new treatments to prevent or halt preterm labor.
• Medical breakthroughs improve the care of premature babies.

About half of premature births result from spontaneous preterm labor, the causes of which are unknown. Infections have long been suspected among the putative causes, however many studies attempting to establish this have been unsuccessful. Although no specific bacterium has been linked to preterm labor, studies suggest that the body's natural immune response to infections may play a role. Infections lead to inflammation, which in turn may cause the release of substances that may trigger labor. 

A number of March of Dimes grantees are seeking to improve understanding of a possible pathway from infection to preterm labor. For example, PRI grantee Michal Elovitz, MD, of the University of Pennsylvania School of Medicine, is studying substances that are involved in the early stages of the inflammatory process in order to develop a blood test that could identify women at special risk. Emmet Hirsch, MD, a PRI grantee at North Shore University Health System in Evanston, Illinois, is investigating how a family of immune system proteins may regulate the processes by which infection may lead to preterm labor. 

Which bacteria or other microorganisms can set off this process remains uncertain. Cultures of the reproductive tract of pregnant women have not revealed any consistent microorganism that could be related to preterm labor. Absence of bacterial growth in cultures has been accepted traditionally as evidence of absence of infection. Recently, however, it has become possible to find microorganisms that may not grow in the traditional culture media. Linda Giudice, MD, PhD, a PRI grantee at the University of California at San Francisco, and David Relman, MD, a PRI grantee at Stanford University are using new genetic technologies to identify microorganisms in the reproductive tract that have eluded traditional cultures. If these efforts identify previously unculturable microorganisms, it will be possible to approach the older question of infection as a cause of preterm labor.