Objective: To determine the rate of PID in women with genital Chlamydia trachomatis infection.
Design: Systematic literature review.
Method: MEDLINE and EMBASE were searched over the years 1975-2003 using the keywords 'Chlamydia trachomatis', 'complication', 'pelvic (inflammatory disease)', 'PID', 'endometritis', 'adnexitis', and 'salpingitis'. The reference lists ofthe articles retrieved were checked for other relevant publications. The PID complication rate was determined, as were the characteristics of the study populations and the validity of the diagnostic methods and outcome measures used.
Results: 9 prospective studies were identified. The rate of PID in women with a genital C. trachomatis infection varied between o and 72%. Asymptomatic women who were diagnosed with C. trachomatis infection in general screening had the lowest rate of PID: 0-4%. PID occurred in 12-30% of symptomatic women or women with a higher risk of having an STD (e.g. visitor of an STD clinic, double-infection with gonorrhoea, high risk assessed by questionnaire, having a partner with symptomatic C. trachomatis infection). Women who underwent legal abortion had the highest rate of PID (27-72%).
Conclusion: The PID rate in women with C. trachomatis varied considerably. Risk depended on whether the infection was symptomatic and the prior probability of having an STD.