New research finds baby's genes, not mom's, may trigger some preterm births

Feb. 3, 2015

Some babies may be genetically predisposed to being born too soon, and variants in the DNA of the fetus—not the mother—may be the trigger for some early births. That is the finding of research conducted by Joseph Biggio, MD, professor and director of the University of Alabama at Birmingham Division of Maternal-Fetal Medicine in the Department of Obstetrics and Gynecology, and his colleagues from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Genomics and Proteomics Network for Preterm Birth Research.

Biggio’s research analyzed the number of copies of certain segments of DNA in the blood or saliva from hundreds of babies and their mothers. No link was established between the number of copies of the mother’s genes and the risk of preterm birth; however, there was a two- to 11-fold increase in preterm births before 34 weeks of gestation among infants in whom any of four genes was duplicated or any of seven genes was deleted.

The preterm birth rate in the United States dropped more than 10 percent between 2006 and 2013, with most of the improvement focused in late preterm births (those between 34 and 37 weeks of pregnancy). Today’s research findings focused on early preterm births—births before 34 weeks of pregnancy—in which there has been little improvement in recent years.

While the differences in the number of copies of the genes or gene regions may not directly cause a preterm birth, they may make a baby more susceptible to infection or reacting to other harmful environmental factors that trigger early labor and delivery, Biggio says.

Read the full story on the UAB website