Objectives: To estimate the prevalence and risk factors of high risk human papillomavirus (HPV) infection in migrant female sex workers (FSW) according to age and geographical origin. Methods: Cross sectional study of migrant FSW attending a sexually transmitted infection (STI) clinic in Madrid during 2002. Information on sociodemographic characteristics, reproductive and sexual health, smoking, time in commercial sex work, history of STIs, HIV, hepatitis B, hepatitis C, syphilis, and genitourinary infections was collected. High risk HPV Infection was determined through the Digene HPV Test, Hybrid Capture II. Data were analysed through multiple logistic regression. Results: 734 women were studied. Overall HPV prevalence was 39%; 61% in eastern Europeans, 42% in Ecuadorians, 39% in Colombians, 29% in sub-Saharan Africans, and 24% in Caribbeans (p = 0.057). HPV prevalence showed a decreasing trend by age; 49% under 20 years, 35% in 21-25 years,14% over 36 years% (p,0.005). In multivariate analyses, area of origin (p = 0.07), hormonal contraception in women not using condoms (OR 19.45 95% CI: 2.45 to 154.27), smoking, age, and an interaction between these last two variables (p = 0.039) had statistically significant associations with HPV prevalence. STI prevalence was 11% and was not related to age or geographical origin. Conclusions: High risk HPV prevalence in migrant FSW is elevated and related to age, area of origin, and use of oral contraceptives in women not using condoms. These data support the role of acquired immunity in the epidemiology of HPV infection and identifies migrant FSW as a priority group for sexual health promotion.H uman papillomavirus infection (HPV) is the commonest sexually transmitted infection (STI) worldwide. More than 20 types of papillomavirus have been associated with cervical cancer, the second cause of cancer related mortality in women globally.1-3 Most HPV infections are asymptomatic and resolve spontaneously with cervical smear abnormalities only occurring in those women with persistent HPV infection.4 5 The advent of molecular biology tools in HPV diagnosis has allowed us to identify HPV infection, differentiate HPV types, and discriminate groups of the population with different risks of infection.2 HPV prevalence depends largely on age and on sexual practices.6-8 The prevalence of high risk HPV ranges from 11% in healthy women in Belgium, 9 20% in female university students in the United States 10 to 36% in Italian women at risk for human immunodeficiency virus (HIV) infection 11 and 46% in Spanish women in prisons.12 The highest prevalences of HPV have been described in female sex workers (FSWs) as they have multiple risk factors for HPV infection, such as young age and multiple sexual contacts. [13][14][15][16] There is wide heterogeneity in reported HPV prevalences in FSW from studies in different geographical areas; 43% in Mexico, 14 48% in Japan, 15 and 63% in Calcutta, India. 16 Over the last few years, an increasing proportion of the FSWs in European countries are mi...