4Orr PH, Brown R, Incidence of ectopic pregnancy and sexually transmitted disease in the Canadian Central Arctic. Int J Circumpolar Health, 1998; 57 (1): 127-134
5Kamwendo F, Forslin L. Epideraiology of ectopic pregnancy during a 28 year period and the role of pelvic inflammatory disease.Sex-Transm-Infect, 2000; 76 (1): 28
6Mcgee ZA, Jensen RL, Clemens CM, Taylor-Robinson D; Johnson AP; Gregg CR; Sex Transm Dis, 1999; 26 (3): 160-165
7Cates WJ, Wasserheit JN. Genital chlamydial infections:epidemioogy and reproductive sequelae. Am I Obstet Gynecol, 1991,164:1771