Incidence, prevalence, and trends of acute pelvic inflammatory disease and its consequences in industrialized countries.

Pelvic inflammatory disease is used herein synonymously with acute salpingitis. In modern industrialized countries, the annual incidence of PID in women 15 to 39 years of age seems to be 10 to 13 per 1,000 women, with a peak incidence of about 20 per 1,000 women in the age group 20 to 24 years. Since 1960 an increase in incidence by a factor of 1.6 to 1.9 has been observed in the age group 20 to 29 years. The incidence of PID is correlated strongly with the prevalence of sexually transmitted diseases, although a fraction of the infections might be of endogenous origin. Use of intrauterine contraceptive devices and operations for legal abortions contribute to the increase in incidence. The prevalence of women in the post-PID state has increased by a factor of about 1.5 since 1960. Women in the post-PID state have a tenfold increased risk for ectopic pregnancy and 25% of the increase in ectopic pregnancy can be accounted for by the increase in post-PID women. Infertility after PID ranges between 5.8% and 60% depending on severity of infection, number of infections, and age of the women. The fraction of women rendered infertile because of PID has increased by a factor of about 1.6 since 1960.