Ovarian cancer is more aggressive and deadly in obese women, scientists have learned.

A study found obesity reduced survival rates, hastened recurrence of the disease, and led to earlier death.

The finding adds to the evidence that being overweight can worsen outcomes for a range of cancers, including breast, womb and colorectal.

Ovarian cancer is one of the most lethal, since it is often only diagnosed at an advanced stage. In 70 per cent of cases the patient will die in five years.

A few recent studies have suggested that obese women with ovarian cancer are likely to have a worse prognosis than those of normal weight.

The new research indicates that this is due to more aggressive tumours rather than delays in diagnosis.

Scientists in the US looked at data from 216 patients with ovarian cancer, comparing 35 obese women with 108 who were of ideal weight.

They found that 29 per cent of obese women and ten per cent of the "ideal weight" group had localised disease.

Obesity was shown to have a significant impact on both disease recurrence and death rates in women with advanced cancers.