ATLANTA – Prenatal screening for chlamydia and gonorrhea is commonly performed in conjunction with Pap testing, which results in low screening rates among those who don’t undergo Pap testing, a retrospective cohort study showed.
These findings are concerning because recent changes in cervical cancer screening recommendations that increase the screening interval for many women could further reduce the rates of screening for chlamydia and gonorrhea if clinicians don’t "untie" Pap testing and STD screening, Dr. Christine Ross said at a conference on STD prevention sponsored by the Centers for Disease Control and Prevention.
Courtesy CDC
13% of the women included in the study population had received neither a Pap test nor a chlamydia or gonorrhea screening test.
Among 63,332 pregnant women with a live birth who were included in a 12-state Medicaid claims database in 2009-2010, 79% were tested for chlamydia, 72% were tested for gonorrhea, and 74% underwent cervical cancer screening by Pap test. Of the 46,966 who underwent Pap testing, 89% and 80% were tested for chlamydia and gonorrhea, respectively, and of those who did not undergo Pap testing, only 51% and 48% were tested for chlamydia and gonorrhea, said Dr. Ross of the division of STD prevention at the CDC.
"We found that 13% of women in our study population had neither a Pap test nor a chlamydia or gonorrhea screening test," she said.
Women included in the current analysis were aged 15-24 years, and were enrolled in Medicaid continuously for at least 210 days at the time of delivery. The women had numerous prenatal visits, and thus had ample opportunity for screening.
The CDC recommends universal chlamydia screening in pregnant women, with screening at the first prenatal visit, and recommends gonorrhea screening of pregnant women at risk, which includes those under age 25 years and those with a prior infection. Repeat screening in the third trimester is recommended for certain high-risk patients.
In 2012 the U.S. Preventive Services Task Force revised its cervical cancer screening guidelines, and screening is no longer recommended in women younger than 21 years. Also, the interval for screening was extended to 3 years for those over age 21 years, Dr. Ross noted.
The findings are concerning for several reasons, she said.
The vast majority of chlamydia and gonorrhea infections are asymptomatic, including those occurring during pregnancy. Studies show that only 5%-35% of patients with laboratory-confirmed infections develop symptoms. Furthermore, both chlamydia and gonorrhea can affect neonates and can lead to adverse outcomes in pregnant women, she explained.
Furthermore, in one large study involving laboratory data for 1.3 million pregnant women, nearly 16% of 16-year-olds tested positive for chlamydia, and 3% tested positive for gonorrhea. The rate of positive tests declined with advancing maternal age – a finding that is consistent with CDC data, Dr. Ross noted.
Yet, under the revised guidelines, the younger women – who are at the highest risk of infection – would be less likely to be tested.
For many years, screening for chlamydia and gonorrhea was performed at the time of Pap testing, using the endocervical sample, but improved understanding of human papillomavirus infection in young women led to the revision of the guidelines.
Although limited by factors inherent in using administrative data, and by the underrepresentation of Hispanics, who comprised only 3.6% of the sample, the current findings suggest that a reduction in chlamydia and gonorrhea screening may be an inadvertent consequence of the changes.
Future studies are warranted to evaluate this potential consequence as more providers implement the new cervical cancer screening recommendations, Dr. Ross said.
"In the meantime, we recommended informing prenatal providers about the importance of screening all pregnant women for chlamydia and those at risk for gonorrhea, and that alternative specimen collection methods that do not require a pelvic examination that is done during a Pap test are available – and in fact are preferred," she said, noting that patient- or provider-collected vaginal swabs are the preferred specimen, and that urine also can be used.
Dr. Ross reported having no disclosures.