Cervical cancer risks increased by sex at an early age

The finding came after experts at the International Agency for Research on Cancer investigated why poorer women have a higher risk of the disease.

Until now, experts thought that the difference in cases of the disease could be just because poorer women were less likely to go for cervical screening.

But researchers now think the difference is largely because poorer women start having sex an average of four years earlier.

Cervical cancer is largely triggered by the presence of the human papillomavirus (HPV) - which is sexually transmitted.

Dr Silvia Franceschi, a lead author of the study from the International Agency for Research on Cancer, said: "We weren't sure why cervical cancer is more common in poorer women.

"Levels of HPV infection were approximately the same across the board and, in some countries, even higher among the richest women.

"We now think that it's because in our study poorer women had become sexually active on average four years earlier.

"So they may have also been infected with HPV earlier, giving the virus more time to produce the long sequence of events that are needed for cancer development."

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: "This study raises some interesting questions.

"Although women can be infected by HPV at any age, infections at a very young age may be especially dangerous as they have more time to cause damage that eventually leads to cancer."