One-Quarter of Vaginal Births Cause Tiny Brain Hemorrhages
But experts say this slight bleeding doesn't cause symptoms and is probably 'normal'
TUESDAY, Jan. 30, 2007 (HealthDay News) -- In news that's sure to concern expectant mothers everywhere, researchers are reporting that as many as 26 percent of all babies born vaginally may experience bleeding in the brain caused by the birthing process.
But, the researchers, from the University of North Carolina School of Medicine, were quick to point out that these findings don't mean that women should opt for Cesarean births, instead. These very small hemorrhages don't cause symptoms and are likely a normal part of delivering vaginally. And it's only because of high-tech imaging that they've now been discovered, the study authors explained.
"This study demonstrates that intracranial hemorrhages are much more common in newborns than expected," said one of the study's authors, Dr. Honor Wolfe, associate professor of obstetrics and gynecology at the University of North Carolina School of Medicine. "For parents and obstetricians, hearing that 26 percent of babies have bleeds in the head is frightening, and it may lead some to conclude that C-section is safer. But, we have no evidence that these bleeds are problems later in life, and women have delivered vaginally for centuries."
Plus, she noted, C-sections have risks as well, especially for the mother. "I don't think patients should change plans for delivery based on the findings in this study."
Results of the study appear in the February issue of the journal Radiology.
Each year, about 4 million babies are born in the United States, according to the U.S. National Center for Health Statistics. Approximately 2.9 million of those babies are delivered vaginally, with the remaining 1.1 million delivered by Cesarean section.
The new study, which included 88 newborns, was originally designed to study normal brain development in infants.
The infants' brains were imaged using the latest MRI technology, which provides very high resolution scans, according to another study author, Dr. Keith Smith, a professor of neuroradiology.
"We need to recognize that this happens commonly after birth and isn't indicating any abnormalities. It's not a cause for alarm. The fact that we're seeing so much higher an incidence is a reflection of the fact that this was done with very high resolution imaging," Smith said.
Still, the researchers were surprised to find that so many babies had evidence of minor bleeding in the brain.
"This finding was pretty unexpected," said Dr. John Gilmore, a study co-author, and a professor of psychiatry.
Gilmore said the researchers went back to see if the type of delivery -- whether forceps or vacuum extraction were used -- or the length of labor increased the risk of hemorrhage.
"There was no association with any of these we thought might be risk factors," said Gilmore. "It seems like it's just the process of being born."
He added that a newborn's skull isn't yet fully formed, so it can compress during delivery. That compression may cause small tears in the baby's blood vessels.
But, Gilmore said there was no evidence that the small bleeds cause any problems. To be sure, he said, they'll follow the babies' progress over the next few years.
Dr. William Blessed is director of maternal-fetal medicine at Providence Hospital and Medical Center, in Southfield, Mich. He called the new research "a very good study, but with small numbers."
"I think this has probably been going on all along. I don't think the prevalence is increasing," Blessed said, adding that the information from this study may help doctors with liability issues. "In the past, people always thought if there was a hemorrhage, the doctor must have done something wrong. Now, you see you can have intracranial hemorrhage without [cause]; it can occur in a normal birth."
Blessed said he's concerned that some patients may want to have C-sections because of this study. He said it's important to remember that these findings were "clinically insignificant."
C-sections, on the other hand, carry known risks because it's a major surgery. "While the risk of complications from C-sections have greatly diminished, there are risks. Some patients do have complications," Blessed said.
Visit the U.S. National Women's Health Information Center to learn more about the labor and delivery process.