The research leader was Professor Alastair MacLennan with laboratory work performed by Dr Catherine Gibson, who was awarded her PhD for this work. The study involved 443 children with cerebral palsy and 883 control babies. All babies were born to white mothers between 1986 and 1999.
Small dried blood samples taken within a few days of birth were used to test for the presence of neurotropic viruses, a group of viruses including the herpes virus, which can all cross the placenta and infect the fetus.
Exposure to viral infection was common in all newborn babies, especially in preterm babies, implying that infection before birth may also be linked to preterm delivery.
Herpes group B viruses were found more often in babies who were later diagnosed with cerebral palsy than in control babies. In fact, the risk of cerebral palsy was nearly doubled with exposure to herpes group B viruses.
"This is the first study to positively link viral exposure during pregnancy with cerebral palsy. However, only a few of the fetuses that were exposed developed CP, and this suggests that some are more susceptible. We are investigating this," said Dr Gibson.
"Despite some limitations, this study shows that perinatal exposure to neurotropic viruses is associated with preterm delivery and cerebral palsy," said Professor MacLennan.
Future studies are planned to investigate the possible causes of this link and to move towards possible strategies to prevent cerebral palsy, which is currently unpreventable.