Obstetricians balk at FDA warning on anesthesia in pregnant women

(Reuters Health) - - Repeated or lengthy use of general anesthetic and sedation drugs in infants, toddlers and pregnant women in their third trimester might damage children’s developing brains, the U.S. Food and Drug Administration warned this month.

Upset that the warning about pregnant women was based solely on animal studies, the American College of Obstetricians and Gynecologists, or ACOG, shot back its objection.

“ACOG is unaware of data on pregnant women that support the FDA’s claims,” the group said in a practice advisory to its members. “These warnings may cause patients and providers to inappropriately reject the use of these medically indicated drugs.”

Dr. Chris Zahn, vice president of practice activity for ACOG, said that the nonprofit, which represents physicians who care for women, and the FDA have had a close working relationship and in the past have discussed similar warnings before they were announced. But the warning about pregnant women and anesthesia was different.

“We were caught entirely off guard, and we are concerned about the practical applicability of this warning and its potentially negative impact on women’s health, particularly pregnant women,” Zahn said in a phone interview.

On December 14, the FDA issued a safety announcement urging that healthcare providers, parents and patients weigh the potential benefits against the risks while considering the timing of non-emergency surgery, particularly for pregnant women in their third trimester and children less than 3 years old (

The FDA based its safety advisory - and a requirement that drug manufacturers add warning labels on 11 anesthetic and sedation drugs - on both clinical human studies and animal studies. But the human studies include only children, not pregnant women.

Studies have shown that more than three hours of general anesthetic and sedation drugs in pregnant and young animals caused widespread loss of nerve cells in the offspring’s brains, FDA spokeswoman Sarah Peddicord said. Research showing adverse effects on behavior and brain development has been done in multiple animal species, from flatworms to non-human primates.

Asked why the FDA included pregnant women without clinical evidence of a problem, Peddicord said, “This is something we have been looking at, and based on the information we have, we thought it was important to get the information to the public.”

At the same time, the FDA announcement seeks to reassure some parents of children contemplating surgery. “Consistent with animal studies, recent human studies suggest that a single, relatively short exposure to general anesthetic and sedation drugs in infants and toddlers is unlikely to have negative effects on behavior and learning,” it says.

The FDA and ACOG both agree that more research is needed. To that end, in 2010, the FDA and the International Anesthesia Research Society created SmartTots, a public-private partnership studying gaps in knowledge about the safe use of anesthetics and sedatives in children.

About 2 million American children undergo anesthesia annually, mostly for common, non-emergency procedures, such as hernia repairs, circumcisions and tonsillectomies.

Dr. Lena Sun, professor of anesthesiology and pediatrics at Columbia University Medical Center in New York City, has been studying the issue in children and said she believes the FDA acted in an abundance of caution.

“We do not need to unduly alarm the public, but we want the public to be aware of this potential risk,” she said in a phone interview.

“While we are pretty sure and reassured that single and brief exposures in healthy children should not raise any concerns, we cannot offer the same reassurance for prolonged and repeated exposures,” she said.

Sun, however, is unaware of any research in humans indicating pregnant women’s exposure to anesthesia could harm the brains of theirnborn children.

Dr. Maurice Druzin, professor of obstetrics and gynecology at Stanford University School of Medicine in California, described the FDA’s inclusion of pregnant women in the advisory as “unfortunate” and “inappropriate fear-mongering.”

“A patient is going to say, ‘wait a minute; I don’t want to have this surgery because it’s going to destroy my baby’s brain cells,’” Druzin told Reuters Health.

In the end, though, he said he expects the warning to have little impact on his obstetrics practice because he rarely uses general anesthetics nowadays.