Risk of cancer with combined oral contraceptive use among Iranian women

Oral contraceptive use is the most common type of contraception. More than 300 million women worldwide
take oral contraceptives every day. However, there is a concern about the relationship with the incidence
of cancer. This analytical retrospective study aimed to investigate the relationship between the incidence of
cervical and breast cancers and oral contraceptive use in 128 Iranian patients with cervical cancer, 235 with
breast cancer and equal numbers of controls. Data were collected through interviews with an organized set of
questions. Details were also extracted from patient files. Data were analyzed using Student’s t-test, chi-square and
Fisher’s exact tests, and Pearson’s correlation analysis. The result revealed correlations between both cervical
and breast cancers and history of contraceptive pills use. While cervical cancer significantly correlated with
duration of use of pills, breast cancer had significant correlations with the type of oral contraceptive and age at
first use. No significant relationships were found between the two types of cancer and age at discontinuation of
oral contraceptives, patterns of use, and intervals from the last use. The use of oral contraceptives may triple
the incidence of cervical cancer and doubles the incidence of breast cancer. Therefore, performing Pap smears
every six months and breast cancer screening are warranted for long-term oral contraceptive users.