盆腔炎性疾病 (PID) 最常见于有性传播疾病史的年轻、单身、性活跃的女性。[2]Grodstein F, Rothman KJ. Epidemiology of pelvic inflammatory disease. Epidemiology. 1994;5:234-242.http://www.ncbi.nlm.nih.gov/pubmed/8172999?tool=bestpractice.com根据临床症状和体征很难明确诊断,因此确切发病率尚不清楚。在美国,每年至少有一百万女性患 PID,[3]Crossman SH. The challenge of pelvic inflammatory disease. Am Fam Physician. 2006;73:859-864.http://www.aafp.org/afp/2006/0301/p859.htmlhttp://www.ncbi.nlm.nih.gov/pubmed/16529095?tool=bestpractice.com并且是最常见的妇科住院原因。[4]Sutton MY, Strenberg M, Zaidi A, et al. Trends in pelvic inflammatory disease hospital discharges and ambulatory visits, United States 1985-2001. Sex Trans Dis. 2005;32:778-784.http://www.ncbi.nlm.nih.gov/pubmed/16314776?tool=bestpractice.com在工业化国家,20-24 岁的女性 PID 的年发病率最高。大多数的病例在门诊确诊。近年来,住院和门诊确诊的病例数量均已减少。[4]Sutton MY, Strenberg M, Zaidi A, et al. Trends in pelvic inflammatory disease hospital discharges and ambulatory visits, United States 1985-2001. Sex Trans Dis. 2005;32:778-784.http://www.ncbi.nlm.nih.gov/pubmed/16314776?tool=bestpractice.com这可能由于衣原体感染的早期诊断和治疗。