Does contraceptive method change the Pap smear finding?

The aim of the present study was to investigate the effect of various types of contraceptives on morphological finding of Pap smear results. Pap smear results of 7,753 fertile women who presented to 15 different family planning services in Fars Province (south of Iran) were analyzed according to their methods of contraception. The population consisted of 2241 women who used intrauterine device (IUD) as a contraceptive method (Group 1), 2521 women who were oral contraceptive (OCP) users (Group 2), and the control group, which consisted of women who used other methods of contraceptive. Comparison between the Pap smear results showed a higher number of benign cellular changes among Group 1 (22.4%) than Group 2 (19.3%), and the differences were statistically significant (p = 0.009). In addition, 80.6% women who used oral contraceptive pill (OCP) as contraceptive showed cellular changes within normal limits, while it were 77.6% for intrauterine device (IUD) users. Compared with Group 2, Group 1 had a significantly higher percentage of metaplastic cells in their Pap smear results (G1 7.4%, G2 5.8%, p < 0.05). No epithelial abnormalities were reported in Pap smears. Trichomonas vaginalis was higher in G1 than the other groups (p < 0.005), but the difference was not statistically significant for candidiasis. It may be concluded that in this population, IUD and OCP had no effect on morphological pattern of the Pap smears, but there was a significant increased rate of trichomonas infection in IUD users.