"If children need to have surgery, you need to weigh all the risks and all the benefits in terms of what you need to do," Sun says.

"I don't want to scare parents," says researcher Lena S. Sun, MD, a pediatric anesthesiologist at Columbia University Medical Center in New York.

However, the study does not prove that anesthesia is the cause.

The new study, which is published in the journal Pediatrics , links even a single dose of anesthesia to later harm.

Recent studies have suggested that anesthetic drugs may increase the risk for learning disabilities and behavioral problems such as attention deficit hyperactivity disorder ( ADHD ), but only in kids who are exposed to the drugs several times.

Aug. 20, 2012 -- A new study is raising fresh concerns about the use of general anesthesia in young children.

Anesthesia Study

The new study is based on data from nearly 2,900 children in Australia followed by researchers since before they were born.

Parents reported that 321 children in the study had medical procedures that required general anesthesia before age 3. The other 2,287 children weren't exposed to the drugs.

When the children were 10, researchers tested how well they could learn, think, remember, reason, and use language. Doctors also asked questions about their behavior and any problems like depression or aggression.

Kids who were given anesthesia before age 3 were more likely to have learning problems by age 10 than other children.

Children who got anesthesia as toddlers, for example, weren't able to use language as well as their peers. They also had more trouble solving problems.

There could be other explanations. Children who need surgery early in life might have other medical conditions that hurt their brain development in some way.

But the researchers say they don't think that's the case since most procedures performed in the study were minor. Those included common childhood surgeries including inserting ear tubes to help kids with chronic ear infections, hernia repairs, circumcisions, removing a child's tonsils, and dental procedures.

Even after accounting for things that are known to have an impact on brain development, such as mom's education, low birth weight, and household income, exposure to anesthesia was still linked to the likelihood that a child would have difficulty using language.

Children exposed to anesthesia were more than twice as likely to have a language disability. In particular, it increased the chance that a child would have trouble listening to and remembering spoken words.

Anesthesia was also tied to a 73% increased chance that a child would have trouble with abstract reasoning. Multiple exposures to anesthesia further raised a child's risk for problems.

The researchers found no link between anesthesia and behavioral problems or attention, however.