A 14-year study published on Thursday claimed that an annual blood test could cut ovarian cancer deaths by one-fifth, The Guardian reported. The trial by University College London is the biggest of its kind till date, inviting more than a million participants from England, Wales and Northern Ireland.

The study suggested that 15 fatalities could be prevented among every 10,000 women screened regularly under their programme, which is roughly a fifth of the current deaths. The new test measures changing levels of a blood protein called CA125, which has been linked to ovarian cancer, the biggest killer among gynaecological ailments.

The researchers divided their sample group of more than 200,000 post-menopausal women into three groups, administering the blood test to 50,000 of them. Another 50,000 were given regular vaginal exams, while the rest were not screened at all. The researchers said the blood test allowed them to recommend further examination at an early stage, as against the other two groups.

However, the researchers said more testing is necessary before the study can translate into a national policy.