Age at first intercourse and HPV immunization.

The licence of the first human papillomavirus vaccine (HPV) has important implications for the most appropriate age for a mandatory immunization. In this paper data taken from a recent study show that more than 10% of the Italian women report having already had a sexual intercourse by the age of 15. There is thus sufficient evidence to recommend administration of the HPV vaccine to all girls by the age of 12.