A new research has predicted that women who use hormonal contraceptives, which involves birth control pills, are at a raised risk of breast cancer. Not only this but the new study also shows that the risk for breast cancer improved with longer use - from a 9 percent increase in risk with less than a year of contraceptive use to a 38 percent increase after more than 10 years of use.

The researchers from the University of Copenhagen in Denmark served that 1.8 million women between 15 and 49 years of age for more than 10 years. They stated that the risk of breast cancer was higher among women who newly used contemporary hormonal contraceptives than among women who had never used hormonal contraceptives. But, absolute increases in risk were small. The study also proves that women who currently or recently used the progestin-only intrauterine system also had a higher risk of breast cancer than women who had never used hormonal contraceptives.

The overall absolute increase in breast cancers diagnosed among current data and recent users of any hormonal contraceptive was 13 per 100,000 persons or about one extra breast cancer for every 7,690 women using hormonal contraception for one year. The findings have been declared in The New England Journal of Medicine.