Doubt surrounding a popular HPV vaccine has some parents of young women unsure about whether they should use a new one going on the market.

The reports about serious side effects with the vaccine known as Gardasil have surprised many. Gardasil has been highly recommended by the medical community and is considered effective in stopping the spread of human papillomavirus, or HPV, which is a sexually transmitted disease associated with cervical cancer.

More than 26 million doses of the vaccine have made their way off pharmaceutical company Merck's production lines and into shots for young women ages 9 to 26. Since June 2006 eight million women and girls in the United States have been vaccinated.

The medical community has considered the vaccine, the first shot to protect a woman from possibly contracting HPV, a breakthrough.

But now reports of severe side effects have surfaced. Some patients are blaming illnesses on the vaccine. Since it was approved in 2006, the federal Centers for Disease Control and Prevention has received 7,802 "adverse event" reports.

Patients and their families have reported cases of nausea, paralysis and at least 10 deaths.

"It's scary, it's almost like more research should be done before doctors are giving out these vaccines," says Mike Abrams, of Stamford.

However, it is not clear whether the vaccine is at fault.

"Right now [we're] in a bit of a state of uncertainly," says Dr. David Lobo, a specialist in infectious disease medicine at Bridgeport Hospital. "But it seems if we follow the CDC and FDA [Food and Drug Administration] recommendations ? the benefits far outweigh the risks."

So far the CDC says none of the deaths are directly linked to the Gardasil vaccine. The federal agency says it continues to study reports of illnesses.

Merck issued a statement saying an "adverse event does not mean that a causal relationship between the event and vaccination has been established, just that the event occurred after vaccination."

HPV Vaccine from Centers for Disease Control