Hormonal contraception and false-positive cervical cytology: is there an association?

The aim of the study was to determine if use of hormonal contraception influences the false-positive rate of cervical cytology when compared with loop electrosurgical excision procedure or cervical biopsy specimens.

We performed a case-control analysis of 328 women referred for colposcopy after an abnormal Pap test. Patients were divided into cases (true-positive cytology results) and controls (false-positive cytology results). Univariate analysis was performed using the chi and Student t test to identify factors associated with false-positive cytology. Multiple logistic regression analysis was used to estimate odds ratios for the independent association of these factors.

The false-positive rate for the entire cohort was 44.8%. Cases were more likely to be pregnant and postmenopausal (odds ratio [OR] = 4.98, 95% CI = 2.16-11.47; OR = 5.48, 95% CI = 1.23-24.36, respectively). Use of hormonal contraception was not significantly different between groups (OR = 0.56, 95% CI = 0.29-1.09 for combination oral contraceptive pills; OR = 0.89, 95% CI = 0.35-2.25 for progestin-containing contraception). Low-grade squamous intraepithelial lesion results were more likely to be false positives (51%) than high-grade squamous intraepithelial lesion (27%) (p <.001).

There remains a substantial lack of correlation between cervical cytology and histology. Use of hormonal contraception was not shown to increase a patient's likelihood of having a false-positive Pap test.