According to a new study in The Journal of the National Cancer Institute, women over 40 years old are unlikely to get significant benefit from an HPV vaccine.  The study examined patterns of HPV infection as women age, screening more than 9,000 Costa Rican women between the ages of 19 and 97 for carcinogenic HPV infections and precursors to cervical cancer.  The study found that the rate of newly detected infections decreased with age, dropping from 35 percent in women 18-25 down to 13.5 percent in women aged 42 and older.  Dr. Ana Cecilia Rodriguez, lead author of the study, explained to The New York Times, “Because the HPV vaccine can only prevent infections [of HPV, and not cervical cancer], and these women are not getting that many new infections, the potential benefit of HPV vaccination among older women is very limited.”  The article can be accessed on the journal’s website.