CHICAGO (AP) -- Medical reports say transgender teens and even younger kids are getting sex-changing treatment at some U.S. clinics.
The numbers are small but on the rise.

These are children who are certain they were born the wrong sex. With their parents' approval, they're getting drugs to stop puberty, followed by sex-changing hormones they must take for life.

One Boston hospital treats about 19 such kids a year and has seen a four-fold increase in patients since 1998. Treatment often starts around age 11.

Some ethicists say the treatment raises concerns. But doctors who provide it say these kids often try suicide or self-mutilation until they get sex-changing treatment.

Reports about the issue were published online Monday in the medical journal Pediatrics.