'Older' age is a risk factor for pelvic inflammatory disease in intrauterine device users

Abstract

Background. To asses the role of a copper intrauterine device (IUD) per se in the development of pelvic inflammatory disease (PID) and complicated PID in women considered at low risk of PID. Methods. Cases were 51 women admitted to hospital with a diagnosis of acute PID, and controls were 50 healthy women attending an outpatient clinic for routine gynecological check-up. The women were 25-45 years old. Data were analyzed and compared between groups using the statistical program package SAS. Results. IUD use was not associated with an increased risk of PID in general, but in women ≥35 years, IUD use was associated with a risk of PID [odds ratio (OR) = 4.2, confidence interval (CI) 1.1-16.3]. When adjusting for smoking, educational level, employment, and microbial findings in women with PID, IUD use was associated with complicated PID in women ≥35 years (OR = 33.9, CI 1.2-959.6), but not in younger women. When adjusting age and IUD use duration for each other in IUD users, age ≥35 years was a significant risk factor for PID (OR = 4.9, CI 1.3-19.2), but not long (≥5 years) duration. In IUD users with PID, age ≥35 years was a risk factor for a PID to be complicated in both the unadjusted and adjusted analysis (OR = 12.7, CI 1.6-102.3; OR = 12.1, CI 1.4-104.7), whereas long duration of IUD use was not. When adjusting for significant endocervical microbial findings, long duration of IUD use and age, only age ≥35 years, remained significantly associated with both PID and complicated PID (OR = 5, CI 1.1-21.9; OR = 36, CI-1.9-670). Conclusions. IUD use was not associated with PID in low-risk younger women, but in women ≥35 years, IUD use was associated with an increased risk of PID. The study also demonstrates an association between IUD use and complicated PID in women ≥35 years. © Acta Obstet Gynecol Scand 2005.