Blue Cohosh Linked to Newborn's Stroke
Mother drank herbal tea in hope of inducing labor
WEDNESDAY, July 14, 2004 (HealthDayNews) -- Just as expectant mothers need to be careful about what medications they take, they should also exercise caution when taking herbal supplements.
That's the conclusion of a case study, which appears in a letter in the July 15 issue of the New England Journal of Medicine. The letter details the story of a baby who had a stroke, possibly because its mother drank blue cohosh tea to induce labor.
"Blue cohosh has been known to stimulate uterine contractions, and was a folk remedy used to initiate labor if a mother was past her due date," said Dr. Richard Finkel, one of the doctors who reported the case and an associate clinical professor in pediatrics and neurology at Children's Hospital of Philadelphia. When this happened, Finkel was a consulting pediatric neurologist at Littleton Adventists Hospital in Littleton, Colorado.
Blue cohosh is from the plant Caulophyllum thallictroides, according to Mark Blumenthal, executive director of the American Botanical Council.
"Blue cohosh is not a widely sold herbal dietary supplement in the U.S.," he said. "Blue cohosh contains teratogenic compounds and the herb has been viewed as relatively toxic, thereby reducing its use in the general market over the past five-plus years."
It should not be confused with the more commonly used herb known as black cohosh, which is used to help control the symptoms of menopause.
According to the research letter, the woman was a healthy 24-year-old in her 40th week of pregnancy. Her obstetrician recommended that she drink a tea made with blue cohosh to hopefully stimulate contractions that would begin her labor. She did so, and did go into labor, Finkel said.
He said the baby initially looked healthy, but then started having seizures. Since a common cause of seizures in infants is stroke, a CT scan was ordered, which confirmed that the infant had, in fact, had a stroke.
When an infant has a stroke, Finkel said there are routine tests doctors run to try to figure out the cause of the stroke, and one of them is a toxicology screen. The results of the toxicology screen on this baby showed a metabolite of cocaine. The test, said Finkel, can't test for cocaine, but instead checks for the compounds that cocaine breaks down into as the body metabolizes it.
When he asked the mother how she thought the baby may have been exposed to cocaine, he said she adamantly denied any drug use and said the only substance she had taken was the blue cohosh tea.
They then tested her bottle of blue cohosh, and it tested positive for cocaine metabolites. Then, Finkel said, the neonatalogist involved in the case purchased a different brand of blue cohosh, and again they found cocaine metabolites in the product.
Finkel said he contacted the U.S. Food and Drug Administration, but because it was an herbal dietary supplement, not a medication, the federal agency "didn't have the authority to follow up." He said if it had been a medication, procedures are in place to report and follow-up on adverse events.
In a search of the medical literature, Finkel said he found another case where blue cohosh was implicated in a bad outcome for an infant. In this case, the infant had a heart attack.
The doctors weren't able to find out if blue cohosh does break down into cocaine metabolites, or if the product had been contaminated somehow with cocaine.
"It remains important to determine if blue cohosh produces a positive assay for cocaine use. Finding cocaine metabolites in the baby and in two different blue cohosh products tends to rule out product adulteration and strongly suggests that the assay results were falsely positive, as they are inconsistent with the known chemistry of blue cohosh," said Steven Dentali, vice president of scientific and technical affairs for the American Herbal Products Association.
However, Dentali also noted that while most herbal dietary supplements are safe, "there are known concerns regarding [blue cohosh's] use in pregnancy. Not all herbs will be devoid of side effects. Pregnant women should be taking safe, non-toxic herbal supplements."
While they weren't able to positively link blue cohosh to the baby's stroke, Finkel said he suspects it played a role.
"Blue cohosh shouldn't be taken in pregnancy," he stressed. "If it's being recommended to initiate labor, women should know that it may not be entirely safe."
To learn more about herbs and pregnancy, go to the American Pregnancy Association.