Sexual behavior, use of contraceptive methods and risk factors for HPV infections of students living in central Italy: implications for vaccination strategies.

The most frequent risk factors related to the infection/persistence of HPV in the population are an early start of sexual activity, the number of sexual partners, smoking, and the utilization of some contraceptive methods. In Italy, HPV vaccine is offered free of charge to all 12-year-old female adolescents, with a possible extension to other age groups according to Regional policies. In order to value the suitability of the current HPV vaccination strategies in Italy, an epidemiological study on sexual habits in adolescents and young adults was organized. An anonymous questionnaire on sexual behavior and risk factors for HPV infection was administered to 2300 students aged 13-24 years attending secondary schools and universities in Tuscany during 2008-09. About 12% of the sample declared to be foreign citizen. The results highlight the early start of sexual activity among young students. Particularly, more than half of the interviewed students declared to be already sexually active. The mean and the median age of the first sexual intercourse was 15.4 +/- 1.4 years and 15 years (25th and 75th percentiles = 14-16), respectively. More than 77% of students at age 16 years declared they already had the first sexual intercourse, compared with 0.3% of those <12 years. Generally, females aged 13-16-years, if sexually active, had sexual contacts with a single partner. Most students declared to know common contraceptive methods (male condom and contraceptive pill). However, only half of them declared a regular use of male condom. These data confirm the importance of vaccination against HPV for young females before their sexual debut. In addition, the current multi-cohort strategy of HPV vaccination in Tuscany (free of charge in the age range 12-16 years) allows also to catch up those girls that have not yet had their first sexual experiences before 16 years (21.5% according to our study) but also to those girls already sexually active, who very rarely are already infected by all vaccine types at 16 years. Our results also show the importance of sexual health education and of promotion of correct behaviours in schools.