The idea behind a plan to vaccinate girls against a cancer-causing virus seems smart.

But some people are concerned that the vaccine, Gardasil, hasn't been tested enough to warrant being mandated -- and they also worry that it puts health decisions in the hands of lawmakers instead of doctors and individuals.

The proposal, sponsored by state Sen. Debbie Halvorson, D-Crete, is expected to come up for a vote later in the legislative session. It would require preteen girls in sixth grade and up to prove to their school districts they've been vaccinated against the human papillomavirus, or HPV.

"I can't in good conscience not do something that I know will eliminate cervical cancer eventually," Halvorson said.

Opponents of the measure say it could cost young girls their reproductive capabilities and parents their parenting. And parents who object to the vaccination face relatively few choices -- if any.

One way out, according to David Smith, executive director of the Illinois Family Institute, is an opt-out clause for parents who don't want their daughters to be vaccinated on medical or religious grounds.

But Smith contends that isn't enough, and the bill should allow every parent the freedom of choice. The solution would be an opt-in clause so parents aren't forced to take this family health issue to the doctor's office, Smith said.

Dr. David Ayoub of the Memorial Medical Center in Springfield agrees.

HPV legislation, which has passed the Senate, not only takes parenting away from parents and puts it in the hands of the state, it also increases the vulnerability of young girls to other health complications such as menstrual irregularities, neurological disorders and infertility, he said.

"Will (Gardasil) affect reproductive capacity? Will it cause birth defects?" Ayoub asked before saying the answers to those questions aren't available.