Women patients within the St. Michael’s Hospital system in Toronto have been 50 percent less likely to get screened for sexually transmitted diseases (STDs) following changes made to Cancer Care Ontario’s cervical cancer test guidelines in 2012, a new study says. The researchers obtained this result after examining patient charts across five primary care locations one year before and one year after the rule change.

Chlamydia is the most commonly reported bacterial STD in Canada, followed by gonorrhea, the researchers observed. Prevalence for both infections is highest among women between the ages of 15 and 24, with rates steadily increasing. The consequences of these infections may be serious, increasing the risk of not only chronic pelvic pain but also ectopic pregnancy… and infertility.

In the past, a woman visiting her doctor to get a Pap smear (a cervical cancer test) gave the physician a chance to discuss sexual health and offer STD screening tests. Before 2012, the guidelines recommended women begin annual Pap smears within three years of becoming sexually active and then, after three consecutive normal results, the recommendation was a test every two to three years until age 70.

However in 2012, Cancer Care Ontario released new guidelines. Screening tests were to begin at age 21, and, given a normal result, tests would occur every three years thereafter. Given that the new recommendations delayed tests while also advocating less frequency, the researchers behind the new St. Michael’s study hypothesized the highest risk women would not be getting screened enough for STDs.

Effects of a Simple Rule Change

Reviewing the charts, the research team found an overall reduction in Pap smear tests by 60 percent (from 42 percent to 17 percent), and a 50 percent decrease in the rates of gonorrhea and chlamydia screening (from 40 percent to 20 percent) among women between the ages of 15 and 24.

“We also found a decrease in screening for syphilis and hepatitis C following the updated guidelines, which can be explained by the same factors mentioned for chlamydia and gonorrhea screening,” wrote the authors. “Although not statistically significant, there was a decrease in HIV screening that was potentially of clinical significance.”

The researchers suggest non-invasive, self-administered swabs and urine tests, which can detect STDs at high rates, be provided in community settings, including high schools, universities, and outreach sites. "Our findings merit concern considering that Canadian rates of chlamydia and gonorrhea rose by
72.0 percent and 53.4 percent, respectively, during the past decade," concluded the researchers.

Source: Bogler T, Farber A, Stall N, et al. Missed connections: Unintended consequences of updated cervical cancer screening guidelines on screening rates for sexually transmitted infections. Canadian Family Physician. 2015.