Oral Contraceptives Protect Against Endometrial and ovarian Cancer

A much longer follow up was carried out compared to the most previous studies to demonstrate that use of oral contraceptive provides a protective effect against the endometrial and ovarian cancers up to 30-35 years after the discontinuation.

This study was performed to explain the time-dependent effects linking the use of long-term oral contraceptive and cancer risk.

It was executed in 256,661 women. Their information on cancer diagnoses was obtained from self-reported data and national registers. The cumulative cancer risk over the study period as calculated by the odds ratio (OR), and immediate risk, as calculated by the hazard ratio (HR), were evaluated with the help of Logistic and Cox regression analyses, correspondingly.

The odds were lesser amongst ever users compared to never users, for ovarian cancer: OR=0.72 and endometrial cancer: OR=0.68.

Augmented odds were observed for breast cancer in women when the follow-up was limited to 55 years of age: OR=1.10 but not for the full period. High HR for breast cancer in former users directly (≤2 years) after the discontinued use of oral contraceptive use (HR=1.55).

The protective association stayed considerable for endometrial and ovarian cancer up to 35 years following the last oral contraceptives use.

The study concluded that oral contraceptives could noticeably decrease the risk of endometrial and ovarian cancer in women. However, their effect on lifetime breast cancer risk is limited. The lifetime risk of breast cancer was not found to be affected by the use of oral contraceptive. This shows that the link between oral contraceptives use and breast cancer is time- and age-dependent.