Brain malformations are significantly associated with preterm birth, according to new research from Wake Forest University School of Medicine.
This is the first time that any team of researchers have found solid evidence of a strong association between congenital brain defects and preterm birth.
The researchers, thus, believe that something about the brain malformations may be causing preterm birth, and could provide a possible study path toward a better understanding of the problem.
"The most important thing about this study is that to-date, it is still unknown why there are so many preterm births. This study suggests that one way to look for the causes of preterm birth is to look at those types of brain malformations that have very strong association with preterm birth, and see if there is some sort of difference between those babies and full-term babies - some sort of soluble factor or an increased amount of something in the preterm babies that is not found in other babies," said Dr. William R. Brown, an investigator for the study.
The study was based on a study of bleeds in the brains of babies, where researchers found that a large percentage of the babies being studied had small, unrecognized types of brain malformations that warranted further investigation.
Although there has been evidence suggesting brain malformations are also associated with preterm birth, it has been difficult to document such an association.
This is because brain defects can be hidden within the cranium and may remain undetected until autopsy, whereas malformations of other parts of the body can be determined through birth registries.
In the study, the researchers looked at 1,168 autopsy files that contained congenital brain defects as well as information on the gestational age at birth of the subject.
It was found that, in the autopsy cases with brain defects, the mean gestational age was 36.6 weeks, whereas the data showed a mean gestational age of 39.9 weeks for infants with no defects and a gestation of 38.1 weeks for infants with defects of any kind.
"Preterm" birth is defined as 20 to 36 weeks gestation, while "term" birth is defined as 37 to 41 weeks.
Only 9.3 percent of babies born without defects were preterm, compared to 21.5 percent of those with defects.
In the autopsy cases with brain defects, the rate of preterm birth was even greater at 33.1 percent, showing the strongest association between the two.
The study showed that some types of brain defects have a stronger association with preterm birth than others.
The study has been published in the journal Pediatric Research.