CDC working on Gardasil study

Gardasil is supposed to prevent certain types of cervical cancer, but since the drug hit the market 2 1/2 years ago, there's been an alarming number of serious adverse reactions and even deaths. According to a federal tracking system, there have been more than 9,700 adverse reactions following the vaccination and 21 reported deaths since 2006.

Merck, the maker of Gardasil, points out that there is no evidence that the vaccine caused or contributed to those events.

Officials at the Centers for Disease Control say the majority of the 8 million girls who have received the vaccine have had no problems.

The CDC says it's working on a comprehensive study which will determine whether there is a pattern linking Gardasil to some of these serious side effects. That study is expected to be released in October.