Bilateral but not unilateral tubal obstruction is associated with positive chlamydia serology

OBJECTIVE: To assess the association between positive Chlamydia trachomatis (C. trachomatis) serology and unilateral or bilateral tubal obstruction. METHODS: This was a cross sectional study that evaluated the association of positive C. trachomatis serology (Immunofluorescence Indirect Serology, IIF or Enzyme Immune Essay, EIE), in two infertile groups: A. 243 patients (27 with unilateral obstruction and 216 without it). B. 247 patients (31 with bilateral obstruction and 216 without it). The exclusion criteria were tubal ligation (tubectomy) and tubal surgery. The statistical test (SPSS 17.0) was the Chi-Square with a p=5%. Tubal obstruction was diagnosed through hysterosalpingography (HSG). RESULTS: The mean age of the patients without obstruction was 33.6 years, SD 4.9. The mean age of the patients with unilateral obstruction was 33.7 years SD 4.9. The mean age of the patients with bilateral obstruction was 33.6 years, SD 4.9. There was no statistically significant difference between the age groups. In group A (unilateral obstruction versus serology) the Chi-Square was 0.02 (p=n.s.) and the Attributable Risk (AR) = 0.7%. In Group B (bilateral obstruction versus serology) the Chi-Square test was 9.87 (p<0.005) and the AR = 14.8%. CONCLUSION: This study found a strong and statistically significant association between bilateral tubal obstruction and C. trachomatis positive serology. The power of the test was 86%. There was no association between unilateral obstruction and positive serology.