“What we know is that if you look at all the women who get an HPV infection, approximately 70% of those are going to clear that infection all by themselves within the first year, with no help from anybody. You don’t have to detect it, you don’t have to make it go away. The body’s going to take over and do it. Within two years, about 90% of all of those HPV infections are going to clear all by themselves.
Now, by three years you’ve got 10% of that original group of women that have HPV infections that are left, and by three years half of those infections have progressed into what we call a CIN2-3 lesion, or a pre-cancerous lesion. So approximately 5% of HPV infections are going to go into a pre-cancerous lesion.
So now you have that small group of women who have pre-cancerous lesions… and now let’s look at that moving into invasive carcinoma. What we know then is that, amongst women with CIN3 lesions… so that’s a little bit more severe than the other group… it takes five years for about 20% of them to become invasive carcinomas. That’s a pretty slow process. It takes about 30 years for 40% of them to become invasive cervical carcinomas.”
—Diane Harper, MD, MPH, MS, lead researcher for Gardasil vaccine trials