But now their findings have been challenged, and one researcher reckons the cancer risk is high, and very real. Prof Joel Brind from New York City University says the findings had been distorted because the original researchers left out sections of the population, including women younger than 38, and current non-users.

The risk increases with length of usage. A woman more than doubles her risk of breast cancer even 20 years after she has stopped taking the pill, and women who have taken the pill for more than eight years also dramatically increase their risk for all cancers.

A woman who has taken the pill for longer than eight years increases her risk of developing cancers of the central nervous system or pituitary system by more than five times.

(Source: British Medical Journal, 2008; 336: 59-60).