[Influence of the use of oral contraceptives as risk factors for human papillomavirus infection and cervical intraepithelial neoplasia].

OBJECTIVE

To study the influence of oral contraception use as risk factor for human papillomavirus infection (HPV) and progression to cervical intraepithelial neoplasia (CIN).

MATERIALS AND METHODS

A prospective, transversal and comparative study of 84 female patients in reproductive age that had used oral contraception for more than three years as birth control method and who had CIN mild (CIN I), moderate (CIN II) or severe (CIN III) associated or not to HPV infection documented by colposcopy, pathology and cytology was done. 84 cases and 60 controls submitted to a directed interrogation were studied. Differences among groups were determined by linear regression, multivariance and logistic regression tests, p <0.05 was considered statistically significant.

RESULTS

Average age for cases and controls was 37.5 and 36.2 years, respectively. The 70% of patients started their active sexual life in the second decade of their life. The most frequent age was 18 and 19 years. 50.6% of these patients had more than one sexual partner, two in average. 67.8% of cases had HPV infection and applying the multivariance analysis: sexual partners (p < 0.05), age at first pregnancy (p < 0.05) and oral contraception use (p < 0.05) were considered statistically significant. According to the CIN grade, the HPV presence was found as highly statistically significant (p < 0.001). Oral contraception use was found as risk factor for HPV infection by logistic regression (p = 0.0242); OR = 3.2714; CI = 1.1670-9.1702. As for the CIN degree, HPV presence was found as highly significant (p = 0.0001); OR = 2.4158; CI = 1.7150-3.4028.

CONCLUSION

A high incidence of HPV was found in our study. This is an important risk factor during cellular transformation, so the use of oral contraception as birth control method could accelerate the viral oncogenes expression present in HPV cellular genome. It is highly recommended to discard HPV infection before prescribing oral contraception as birth control method.