Even a single dose of HPV vaccine in young women is associated with a reduced incidence of preinvasive cervical disease, a study shows.

Receiving one, two or three doses of HPV vaccine in girls aged 15-19 is associated with a reduced incidence of preinvasive cancer, according to research using US health insurance data.

Numerous studies of the protectiveness of various numbers of doses of HPV vaccine have yielded mixed results. For females starting vaccination after age 15, three doses are still recommended at zero, 1-2 and six months.

Researchers examined the association of one, two and three or more doses of the quadrivalent HPV vaccine with cumulative incidence rates of histopathologically confirmed cervical intraepithelial neoplasia (CIN) II/III and high-grade cytology — high-grade squamous intraepithelial lesions (HSILs) or atypical squamous cells (ASC-H).