NEW YORK,(Reuters Health) -- Infants delivered through surgical
procedures including forceps deliveries, vacuum extraction, and cesarean
section, are at increased risk for bleeding in the head and brain, according to
a study of nearly 600,000 infants.
Yet it's unclear whether the procedures alone are responsible for newborn
head injuries. In Thursday's issue of The New England Journal of Medicine,
researchers led by Dr. Dena Towner, of the University of California, Davis,
report that the abnormal labor that prompts these delivery procedures may be to
blame for some of the bleeds.
"The speculation is that something during labor causes the injury well
before delivery, and it is not the mode of delivery that causes all bleeds,"
Towner told Reuters Health.
Her team found that among all infants born to first-time mothers in
California between 1992 and 1994, one-third of deliveries involved one of these
procedures. About 20 percent were delivered by cesarean section; 10 percent by
vacuum extraction; and 3 percent by forceps. Compared with infants delivered
naturally, all of these babies were 2.5 to 3.5 times more likely to suffer
intracranial hemorrhage, depending on the procedure. Delivery using both forceps
and vacuum extraction carried the highest risk -- more than seven times the
risk. Other birth complications, such as breathing problems and temporary nerve
damage, were also more common among infants delivered surgically.
But overall, complications were rare, with intracranial hemorrhage
occurring in less than one percent of infants. And Towner and colleagues report
that infants delivered by cesarean before labor had begun had no increased risk
of intracranial hemorrhage. This, they concluded, suggests that the mode of
delivery "is not necessarily the primary factor" in causing the injury. Towner
noted that factors such as fetal distress and severe infection also cause
intracranial hemorrhage. This bleeding, she noted, rarely leads to death, but is
associated with cerebral palsy and developmental delays.
When labor is unsuccessful in achieving delivery, doctors must choose
between performing a cesarean section or an assisted vaginal delivery, Dr.
Thomas J. Benedetti, of the University of Washington in Seattle, notes in an
editorial published with the report. This study's most important finding,
according to Benedetti, is that the risk for intracranial hemorrhage appears to
be no higher with assisted vaginal delivery than with cesarean.
In 1998, Benedetti notes, the Food and Drug Administration advised doctors
to perform vacuum extraction only in certain instances. This came after the
agency received reports of 12 deaths and nine serious injuries during vacuum
extraction over the previous four years.
This study, Benedetti writes, suggests that there is an "apparently irreducible" number infant injuries due to abnormal labor, rather than the mode of delivery. However, he notes, these findings should be interpreted with caution, and obstetricians must "gather all the available data" to be able to decide whether a mode of delivery will be successful.
