The burden of genital warts: a study of nearly 70,000 women from the general female population in the 4 Nordic countries.

OBJECTIVE: To assess the burden and correlates of genital warts in women.
METHODS: We conducted a population-based cross-sectional study in 69,147 women (18-45 years of age) randomly chosen from the general population in Denmark, Iceland, Norway, and Sweden. Information on clinically diagnosed genital warts and lifestyle habits was collected using a questionnaire.
RESULTS: Overall, 10.6% reported ever having had clinically diagnosed genital warts. In addition, 1.3% reported having experienced genital warts within the past 12 months. The cumulative incidence for different birth cohorts, estimated on the basis of age at first diagnosis of genital warts, increased with each subsequent younger birth cohort (P<.01). The lifetime number of sex partners was strongly correlated with a history of genital warts (odds ratio for > or =15 partners vs. 1 partner, 9.45 [95% confidence interval, 7.89-11.30]). The likelihood of reporting genital warts also increased with a history of sexually transmitted disease, use of hormonal contraceptives, use of condoms, smoking, and higher education.
CONCLUSIONS: The data suggest that 1 in 10 women in the Nordic countries experience genital warts before the age of 45 years, with an increasing occurrence in younger birth cohorts. These data are important for developing and evaluating strategies (e.g., human papillomavirus [HPV] vaccination) to control and prevent HPV infection and disease in the population.