Serum-specific antibodies for Chlamydia trachomatis in premature contractions.

A case-control study was undertaken to examine the possible morbidity associated with Chlamydia trachomatis in 28 pregnant women having idiopathic premature contractions, in 35 healthy preterm pregnant women, and in 43 healthy pregnant women at term. Serum C. trachomatis IgG- and IgA-specific antibodies were determined by the single serovar inclusion immunoperoxidase assay. There were no significant differences in the prevalence rate of elevated C. trachomatis IgG-specific antibodies (titer greater than or equal to 1:128) between pregnant women suffering from idiopathic premature contractions as compared with healthy preterm and term pregnant women (11%, 28%, and 26%, respectively). The known prevalence rate in a normal healthy population is 23%. The prevalence rate of elevated C. trachomatis IgA-specific antibodies (titer greater than or equal to 1:16) was significantly lower in the pregnant women with idiopathic premature contractions as compared with the healthy preterm and term pregnant women (0%, 20%, and 17%, respectively; p less than 0.002 and p less than 0.012). These findings do not support the assumption that C. trachomatis has a role in premature contractions.