A: Cancer of the cervix is extremely rare under the age of 30, with 95 per cent of the 1,000 or so women who die from the condition every year being in their late thirties or older.

Smear tests are good at picking up pre-cancerous changes in the cervix, but they have a high false-positive rate. Many of the “abnormalities” they identify are innocent and will never turn cancerous. Changes in the cervix that occur in women during their teens and early twenties make these false positives more likely and this, and the tiny risk of picking up anything serious, is the reasoning behind the decision to delay smear tests until the age of 25. In Wales and Scotland they start at 20.

Cancer of the cervix is a sexually transmitted disease. Nearly all cases are caused by infection with the human papilloma virus (HPV) - spread by penetrative sexual intercourse, oral sex and other forms of foreplay. The earlier you become sexually active, and the more partners you have, the higher the chances of developing cancer at a young age.

The HPV vaccine should reduce the number of cases in the UK. It is routinely offered to all 12 and 13-year-old girls to protect them before they become exposed to HPV, and there is a catch-up programme to protect all teenage girls up to the age of 18.

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