Women who have given birth to five or more children and who had the second child within a year of the first, have significantly higher risk of developing advanced ductal breast cancer, according to research.
A study of around 30,000 women showed that women who had a gap of less than a year were 5.2 times more likely to develop the cancer than those who had a gap of longer than three years.
The study, which was carried out by the Finnish Cancer Registry and other centres, appears in the British Journal of Cancer. It has been called a ‘major breakthrough’ in the fight against breast cancer.
However, the team of researchers remains unclear as to why the risk increases. Factors such as being overweight and choosing whether or not to breast-feed could have affected results.
Senior science information officer at Cancer Research UK Josephine Querido said women should not be concerned about the study as the ‘results are not conclusive’.