OBJECTIVE: To evaluate the relationship between Neisseria gonorrhea and Chlamydia trachomatis screening strategies and risk of pelvic inflammatory disease (PID) after intrauterine device (IUD) insertion.
METHODS: We conducted a retrospective cohort study of all IUD insertions at Kaiser Permanente Northern California from January 2005 to August 2009. The PID incidence within 90 days after insertion was compared among women who were and were not screened for N gonorrhea and C trachomatis. The study was powered for equivalence with a PID risk difference of −0.006 to 0.006 between two groups considered to be clinically insignificant. Risk difference was calculated by subtracting the proportion of females with PID in one screening group from the proportion of females with PID in the comparison screening group.
RESULTS: Of 57,728 IUD insertions, 47% were unscreened within 1 year of insertion; of screened women, 19% were screened on the same day. The overall risk of PID was 0.54% (95% confidence interval [CI] 0.48–0.60%). Nonscreening had an equivalent risk of PID as any screening (risk difference −0.0034, 95% CI −0.0045 to −0.0022), and same-day screening was equivalent to prescreening (risk difference −0.0031, 95% CI −0.0049 to −0.0008). The equivalence persisted when adjusted for age and race and when stratified by age younger than 26 years and older than 26 years.
CONCLUSION: The risk of PID in women receiving IUDs was low. These results support IUD insertion protocols in which clinicians test women for N gonorrhea and C trachomatis based on risk factors and perform the test on the day of insertion. These findings have potential to reduce barriers to IUD use for women seeking highly effective, long-term, reversible contraception.
LEVEL OF EVIDENCE: II
Risk factor&#x2013;based Neisseria gonorrhea and Chlamydia trachomatis testing on the same day as intrauterine device insertion is associated with a low risk of pelvic inflammatory disease.
Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, Bixby Center for Global Reproductive Health, San Francisco, Kaiser Permanente Northern California, Division of Research, Oakland, and Kaiser Permanente, Walnut Creek Medical Center, Walnut Creek, California.
Corresponding author: Carolyn B. Sufrin, MD, MA, San Francisco General Hospital, Department of Obstetrics and Gynecology, 1001 Potrero Avenue, Ward 6D, San Francisco, CA 94110; e-mail: email@example.com.
Funded by the Kaiser Permanente Northern California Residency Program, Kaiser Foundation Hospitals.
The authors thank Christine Dehlendorf, MD, MAS and Philip Darney MD, MsC, at the University of California at San Francisco (UCSF) for their through and critical review of the article and Eric Vittinghoff, PhD, at UCSF for review of the statical approach. The following individuals made significant earlier contributions to refining the study design: Amy Voedisch, MD, MPH, who worked at Kaiser Permanente Sants Clara at the time of her assistance, and Alice Pressman, PhD, and Fiona Sinclair, MA both of the Kaiser Permanente Division of Research.
Presented at the annual meeting of the Association of Reproductive Health Professionals and the Society for Family Planning, “Reproductive Health 2010,” September 22–25, 2010, Atlanta, Georgia.
Financial Disclosure The authors did not report any potential conflicts of interest.