Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 40 2 2002 06 15 79 82 Salari MH Badami N 2015 09 28 Females abortion is one of the most important sequela of genital infection with chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum.In this study frequency of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum was studied in 125 females with habitual abortion by direct and indirect immunofluorescence tests and culture method and compared with 250 normal population. The results obtained were as follow: Mycoplasma hominis was isolated from 18 (14.4%) females with habitual abortion and 18 (7.2%) normal population (P=0.0139). Ureaplasma urealyticum was isolated from 39(31.2%) females with habitual aboration and 48 (19.2%) normal population (P=0.0045). Chlamydia trachomatis was detected by direct immunofluorescence test in 9 (7.2%) of cases and 2 (0.8%) of control groups (P=0.0002). the antibody titer against D-K serotypes of Chlamydia trachomatis was also measured. The valuable titer of antibody (>1/16) was detected in 15 (12% of cases and 8 (3.2%) of control groups (P=0.0004).The results show that chlamydia trachomatis and Ureaplasma urealyticum may be responsible for some cases of abortion. https://acta.tums.ac.ir/index.php/acta/article/view/2585 https://acta.tums.ac.ir/index.php/acta/article/download/2585/2569