A connection has been known but the scientific basis has not been strong. It is important information for women as negative consequences are often associated with contraceptive pills.

The pill has positive effects besides protecting against pregnancy says Elisabeth Angvall Lundqvist professor in gynekology.
The study also shows that the risk of uterine cancer lessens the longer period a woman takes the pill. After 5 years the risk is 25% less and after 10 years the risk is 50% less. After women stop taking the pill some prophylactic effect continues for at least 30 years. The exact reason for this effect is not known.