Injectable contraception poses transient cancer risk

The case-controlled study by researchers at the Australian National University involved more than 3500 black women in South Africa.

Co-author Professor Emily Banks said the findings should reassure Australian women, as those using hormonal contraception tended to have low background risk for breast and cervical cancers, being both young and having access to screening.

“What you have is a slight transient increased risk,” she said. “[But] in Western countries the net effect is likely to be protective.” 

Injectable contraception was linked to 1.83 times the risk of breast cancer, and OC to 1.58 times the risk, compared to non-users of hormonal contraception. Cervical cancer was 1.58 times higher for injectables and 1.38 times higher for OC.

Women who had stopped taking the pill 10 or more years ago had no increased risk. The study showed a protective effect for ovarian and endometrial cancer after five years of