Possible risk factors for abnormal Papanicolaou smear were investigated in a population-based cross-sectional study. From Nuuk (Greenland) and Nykøbing Falster (Denmark), random samples of 800 women aged 20-39 years were drawn. Totals of 586 and 661 women were included in Greenland and Denmark, respectively. All women went through a personal interview, and had a gynecologic examination including a PAP smear and cervical swab for HPV analysis. A blood sample was taken for analysis of HSV type specific antibodies. Multiple sexual partners was the most important risk factor for abnormal cervical cytology (OR = 4.2). An infectious etiology was also indirectly supported by a relatively protective effect of barrier contraceptive methods (OR = 0.6). The simultaneous finding of HPV 16/18 as a significant risk factor (OR = 2.4) cannot be taken uncritically as support for a causal effect of this HPV type, since such a relationship between cytological changes of the cervix and HPV infection could also emerge if the positive PAP smear was not just a measure of intra-epithelial neoplasia but also an expression of the infection itself on the cervix.