Study shows no link between HPV vaccine and blood clots

A vaccine that protects against four strains of the human papillomavirus, which can lead to cervical cancer, does not increase the risk of blood clots in women, researchers said Tuesday. The findings in the Journal of the American Medical Association (JAMA) are based on 500,000 girls and women aged 10 to 44 who received the HPV vaccine between 2006 and 2013. Using data from national registries, researchers in Denmark found no evidence of an increased risk of venous thromboembolism (VTE) in the 42 days after the shot, which they defined as the main risk period. Of the 500,000, there were 4,375 cases of blood clots, and of those, 889 had been vaccinated during the study period.