Liberman E, et. al. Epidural, Maternal fever and neonatal sepsis evaluation,
Pediatrics, 1997;99:415-420

Babies and their mothers who received epidurals during labor
have higher temperatures, leading to sepsis testing for infants

"The testing process to see if the newborns have sepsis [infections] is extremely painful because it involves drawing vial of blood and sometimes doing a lumbar puncture [spinal tap] to remove fluids from the infant's spine," she said. "It can become an ordeal for the infant."

May 1997

Study Results

The study found that about 14% of women given bupivacaine and fentanyl developed a fever of at least 100.4 F during labor and another 38% were in labor for more than 12 hours after their membranes ruptured. Thirty-four percent of their babies received lumbar punctures [spinal tap], and of that number, about 15% were treated for sepsis.

By sharp contrast, however, only 1% of the other group who opted for different or not medication suffered a fever and only 8% had a long labor. But only about 10% of their babies were tested for sepsis and of those, only 4% were treated.

Overall, 63% of the women (1,047) studied received epidurals, but their number accounted for 96% of those who developed fevers during labor. Their babies accounted for around 86% of all newborns tested for sepsis and about 87% of those given some form of antibiotics.

However, one thing the study could not positively conclude was that epidural either cased infections or increased the risk of actual infections in the newborn, the authors stress.

Also, the study did not review whether the newer kinds of "walking" epidurals would show the same effects as the ones in the study. These epidurals use a different mix of drugs in lower does than the standard epidurals, the authors said.

The study's researchers said doctors must find a better way to identify which newborns need a lumbar puncture. A baby is not in danger unless the mother has an infection, but it is difficult to identify which women have infections because many telltale signs like elevated white blood cell count and abdominal tenderness are normal characteristics of women in intrapartum [i.e., during labor].

Epidurals account for almost 32% of medication given to intrapartum [labor] patients [editor's note: epidural statistics for 2003 identify use as 63%, or double the rate of 1997]. For more than a million [now 2 million] women epidurals are the drugs of choice because they allow women to be awake and push during intrapartum and are less likely than some other drugs to reach the fetus.

Pervious studies have documented an increase in intrapartum temperature [i.e., a 'fever'] associated with the use of epidurals.

Estimates in the rate of rise of maternal temperature from epidurals range from 0.08 degrees per hour to 0.14 degrees/hr. It has also been suggested through these studies that fetal harm may result from maternal temperature elevation [fever] during labor. One study measuring fetal skin temperature during labor found that in 9% of the cases reviewed where the mother was given an epidural, fetal skin temperature reached 39 degrees centigrade [approximately 103.6 degrees F], as compared with the non-epidural group in which no fetuses had as high a skin temperature.

They suggest that as fetal core temperature is likely to be 0.75 degrees C. [approx. 1 1/2 degrees F.] higher than fetal skin temperature, core temperature [of the baby] may sometimes reach 40 degrees C. [approx. 105 degrees F.], a temperature that in adults is associated with heat stroke risk. 

Ellice Lieberman, MD, the study's lead author and director of obstetrics and perinatal epidemiology at Brigham and Women's, said she does not want to stress-out young mothers-to-be with her findings, but feels all women should have this information when deciding on an epidural.

"The testing process (to see if the newborns have sepsis [infections]) is extremely painful because it involves drawing vials of blood and sometimes doing a lumbar puncture [spinal tap] to remove fluids from the infant's spine," she said. "It can become an ordeal for the infant."

Lieberman also said the research finding can be of great benefit to pediatricians who will be able to better distinguish and evaluate which infants are actually infected with sepsis.

Another of the report's authors, Steven Ringer, MD, director of newborn services at Brigham and Women's, has begun a new study to identify which babies can safely do without a sepsis work-up following their birth.

"New mothers keep looking for a magic bullet that says this is an infected baby and this is not an infected baby, but so far we have not found one yet," he said.

For more information:   Liberman E, et. al. Epidural, Maternal fever and neonatal sepsis evaluation,
Pediatrics, 1997;99:415-420