Canadian women who are obese are considerably less likely to get screened for cervical cancer, a new University of Alberta study says.

In a national survey of almost 38,000 women, researchers found that obese women were 30 to 40 per cent less likely to get cervical cancer screening compared to women of normal weight. The findings are published in the August edition of the American Journal of Preventive Medicine.

"As obesity is associated with higher rates of some types of cancer, it's important to determine if the presence of obesity influences the use of screening tests," study author Raj Padwal, of the University of Alberta's Faculty of Medicine and Dentistry, said in a statement.

Padwal said the survey showed that obese women were twice as likely as normal-weight women to say that fear, such as fear of pain, embarrassment or an unfavourable test result, was the reason for not having a pap smear, the test that can show an abnormality that might indicate the presence of cervical cancer.

Previous research conducted in the United States has found that obese people are less likely to get tested for breast, colon and cervical cancer. So the University of Alberta team conducted its own survey of Canadian women to see if the statistics would be similar north of the border.

The study did find that overweight and obese women are being screened for breast and colon cancer at the same rates as normal-weight women.

"I am reassured that for mammograms and colorectal cancer screening, the presence of obesity doesn't impact their use, which is different from reports in other countries," Padwal said.

"However, the gap with pap smears is concerning."

The researchers surveyed women aged 20 to 69. In addition to providing their Body Mass Index, participants were asked to indicate if they have a family doctor and how often they get breast, colon and cervical cancer screening. They were asked to provide a reason if they did not undergo regular screening.