Cancer Care Ontario says women who are sexually active should start regular screening at the age of 21.
It says screening for women under the age of 21 is no longer recommended; cervical cancer rarely occurs under that age.
Young women who are not sexually active by the age of 21 should delay cervical cancer screening until they start having sex.
The new guidelines say once women start to be screened, they should have a Pap test every three years until the age of 70, regardless of whether they are still sexually active or not.
The new statement says women over the age of 70 who have had three or more normal tests in the previous decade can stop having regular screening tests.
The new guidelines make several changes to Ontario's recommendations for cervical cancer screening. Prior to this, young women were told they should have a Pap test within three years of starting sexual activity, regardless of the age at which they started.
And the previous guidelines said women who had a negative screening result should be retested every two to three years. The revised guidelines set the interval at three years.
Cervical cancer is caused by certain strains of human papillomaviruses, which are transmitted through sexual contact. Transmission can occur through digital or oral sexual activity, not simply via intercourse.
A Pap test — named after inventor Georgios Papanikolaou, a Greek doctor — looks for abnormal cells on the cervix.
Cervical cancer is generally curable if caught in the early stages. Deaths to cervical cancer in Ontario have plunged by 60 per cent in the past 30 years due to widespread screening.
Still, it is projected that 550 women in Ontario will be diagnosed with cervical cancer this year and 160 women will die from the disease.