A baby's first experience in the world may be a bit of a shock, or even a big headache. No one really knew how much a vaginal birth could strain the brain until University of North Carolina researchers took sharp images of some infants’ brains afterward.

UNC psychiatrist Dr. John Gilmore and radiologist Dr. Keith Smith studied babies at high risk of developing schizophrenia. They were compared to magnetic resonance images of normal babies.

However, the normal infants showed small white spots on their brains that indicated bleeding.

“We unexpectedly found that about 25 percent of babies that were born vaginally had intracranial hemorrhages, or bleeds in and around the brain,” Gilmore said.

“Babies have been having to squeeze through the birth canal for a long time, but this is the first time we've looked at it with these very sharp pictures,” Smith said.

They couldn't find any special cause for the bleeding, like having an unusually long delivery or needing forceps or vacuum suction to deliver the baby. Most of the bleeds were small and didn't cause any long-term problems, but large bleeds can cause symptoms and could require surgery.

“Twenty-five percent of us were having these bleeds when we were born and we're doing just fine, so it's probably nothing to worry about,” Gilmore said.

The UNC researchers will continue to follow the growth and development of the normal babies with brain bleeds in their study.