Effect of the menstrual cycle and hormonal contraceptives on human papillomavirus detection in young, unscreened women.

OBJECTIVE

To estimate the effect of the menstrual cycle and oral contraceptive pill (OCP) use on the prevalence, incidence, and persistence of human papillomavirus (HPV).

METHODS

A longitudinal study was conducted among 2,065 women aged 18-29 years. The women returned a self-collected cervicovaginal sample and filled out a questionnaire. A total of 1,812 women participated at all three time points, month 0, month 6, and month 12.

RESULTS

Low- and high-risk HPV prevalence at study entry was 8.9% and 11.8%, respectively. The annual incidence of low-risk HPV infections was 12.5% and the persistence was 2.0%. For high-risk HPV, the incidence and persistence was 12.1% and 4.5%, respectively. These results did not differ between OCP users and nonusers. A significant relationship between high-risk HPV detection and the timing of sampling was found when OCP users and nonusers were analyzed separately. In the second half of the menstrual cycle, high-risk HPV detection decreased in nonusers (P=.007) and increased in OCP users (P=.021). When women used OCPs continuously, high-risk HPV detection returned to the level of the first half of the menstrual cycle.

CONCLUSION

High-risk HPV detection was significantly influenced by sample timing in the menstrual cycle when analyzed separately for OCP users and women with a natural menstrual cycle. This may have implications in the future, when high-risk HPV detection may become a primary screening tool in cervical cancer prevention.

LEVEL OF EVIDENCE: II.