Background and Aims: Endometriosis is considered to be one of the most common women's diseases in the world. The exact cause of endometriosis is unknown. In this study, the bacterial agents were considered as the probable factors influencing this disease and the frequency of two bacteria U. urealyticum and C. trachomatis was studied in this disease. Materials and Methods: This study was performed on Pap smear samples of 50 women with endometriosis, 48 healthy women referred to hospitals in north of Tehran. The recommend samples were transferred to the laboratory, their DNA was extracted, and PCR method was performed. They were analyzed by descriptive statistics. Results: Performing PCR test for U. urealyticum detection among the pap smears of people with endometriosis and non_endometriosis, 27 samples (54%) and 25 samples (52%) were positive respectively but none of the samples had contamination with C. trachomatis. The highest prevalence of U. urealyticum in both endometriosis and healthy subjects was observed in the age group of 30-35 years. Conclusion: The prevalence of U. urealyticum in patients with endometriosis and healthy subjects (non_endometriosis) was relatively similar and the same as normal flora. There was no infection with C. trachomatis in these individuals, therefore there was no significant association between these bacteria and endometriosis. For more accurate results such studies should be done in a higher statistical society.

Chlamydia trachoma is infection is the most common sexually transmitted disease all around the world. For a long time, Chlamydia trachoma is has been recognized as the common cause of urethritis, cervicitis, and other complications such as pelvic inflammatory disease (PID), ectopic pregnancy, etc. However, today there is more concern on its role in male and female fertility and infertility and many studies have concentrated on this issue all over the world. There is good evidence based on seroepidemiologic studies on relationship between serum Chlamydial antibodies and infertility due to tubal factor in women with or without PID. However, there are many questions about Chlamydia trachoma is and its influence on IVF outcome and the existing information is controversial. The impact of Chlamydia trachoma is on male infertility is under investigation and it seems able to cause destruction of different parts of male genital tract in addition to high rate of transmission to women. With regard to these data, it seems that prevention, early diagnosis and treatment of Chlamydial infections are important and cost effective.