A new federal guideline that lets health insurers deny new coverage to children except those who sign up during “open enrollment” has drawn fire from the child advocacy group First Focus.

On Tuesday, the U.S. Department of Health and Human Services (HHS) granted a request by health insurance companies to declare that the new federal health care law does not require them to enroll children outside of the companies’ specific open enrollment periods, which generally occur once a year.

“Issuers in the individual market may restrict enrollment of children under 19, whether in family or individual coverage, to specific open enrollment periods if allowed under State law,” HHS said.

That prompted Bruce Lesley, president of First Focus, to issue a statement saying, “Insurance companies are using America’s children as a pawn to further their bottom lines.”

He called on HHS to  “issue further guidance in order to prevent insurance companies from unfairly limiting access to coverage for those children who need it most.”

Insurance companies had said that without the clarification, parents would essentially be encouraged to avoid enrolling their children when they are healthy, but to enroll them outside of open enrollment periods when the children get injured or sick – thus immediately costing the insurance companies money for claims.

Meanwhile, in testimony before the House Subcommittee on Children and Families yesterday, Obama administration officials said more children are insured now than ever before.