To study the possible association between use of oral contraceptives and human papillomavirus infection.
We studied a cohort of female Helsinki University students (n=28,109) and other female university students (n=9,044) in the Helsinki area, born in 1946-1960 [1]. Our study material consists of 706 students (controls of an earlier breast cancer and oral contraceptives study) [1]. Linking the study material to the serum bank of the Finnish Maternity Cohort [2], we identified 297 women with stored first trimester serum samples. HPV type 16 and type 18 and Chlamydia trachomatis antibody analyses were done [3,4], and seropositivities used as measures of cumulative incidence of HPV16/18 and C. trachomatis infections. Data on oral contraceptives, smoking, parity, BMI and alcohol use were available for the cohort [1].
Prolonged OC use for five years or more was non-significantly associated with increased risk for HPV16/18 seropositivity (odds ratio adjusted for age, smoking and C.trachomatis 2.6 with 95% confidence interval (0.8−8.5).
In conclusion, there is probably an association between the use of oral contraceptives and HPV16/18 infection. However, further studies using large scale follow up data are required to properly assess the association between OC use and the acquisition of HPV16/18 infection.
1. Hemminki, E., Luostarinen, T., Pukkala, E., Apter, D., Hakulinen, T. (2002). Oral contraceptive use before first birth and risk of breast cancer: a case control study. BMC Womens Health, 2, 9.
2. Koskela P, Anttila T, Bjørge T, et al. Chlamydia trachomatis infection as a risk factor for invasive cervical cancer. Int J Cancer 2000;85(1):35-9.
3. Luostarinen T, af Geijersstam V, Bjorge T, et al. No excess risk of cervical carcinoma among women seropositive for both HPV16 and HPV6/11. Int J Cancer 1999;80(6):818-22.
4. Luostarinen T, Namujju PB, Merikukka M, et al. Order of HPV/Chlamydia infections and cervical high-grade precancer risk: a case-cohort study. Int J Cancer 2013;133(7):1756-9.