Gardasil is supposed to prevent infection by certain strains of HPV virus, which in rare cases may cause cervical cancer if left untreated.
However, trial data from Merck shows that Gardasil vaccinations may actually increase your risk of cervical cancer by 44.6 percent if you have been exposed to HPV strains 16 or 18 prior to vaccination.2 The U.S. Food and Drug Administration has made this document inaccessible, but we've saved a copy of it. In his Slate article, investigative journalist Frederik Joelving recounts the story of Kesia Lyng, a 30-year-old Danish woman who, at the age of 19, participated in a clinical trial for Merck's Gardasil vaccine
"Lyng's grandmother had died of cervical cancer the year before, so when a letter arrived offering her $500 to take part in a crucial international test of Gardasil, the decision was easy," Joelving writes. "She got her first shot of the vaccine at Hvidovre Hospital in Copenhagen on September 19, 2002. The symptoms snuck up on her shortly after her second shot on November 14.