A provision of the health care bill that bars health insurers from refusing to cover sick children [1] with pre-existing conditions will go into effect on Thursday [2], and several of the nation's largest health insurers, anticipating the change, have found a way to avoid bearing the law's full effect.

Many have dropped child-only policies altogether, in states where they're allowed to. Because the health care overhaul prevents insurers from turning down coverage of kids, insurers are afraid parents will wait until their children are sick to enroll them. In August, the Obama administration issued a clarification [3], allowing insurers to restrict enrollment of children to particular "open enrollment" periods, if allowed by state law.