Postabortal pelvic infection associated with Chlamydia trachomatis and the influence of humoral immunity.

Among 1101 women undergoing legal abortion by vacuum aspiration within 14 weeks of gestation, 69 (6.3%) harboured Chlamydia trachomatis in the cervix and/or urethra. Of the chlamydia-positive women, 16 (23.2%) developed endometritis and 10 (14.5%) developed salpingitis during the first postoperative month. The corresponding figures among the chlamydia-negative women were 59 (5.7%) and 5 (0.6%). These differences are highly significant (p less than 0.001). To study the significance of systemic and local humoral immunity to C. trachomatis in these complications, chlamydial antibodies were determined in serum and cervical secretions. No difference in frequency of local IgA antibodies in chlamydia-positive women was observed between those with and those without complications. On the other hand, there was a strong indication that chlamydia-positive women who developed salpingitis had a lower mean titer (17) of serum IgG chlamydial antibodies than carriers without symptoms (82, p less than 0.02). The group of endometritis patients did not differ in this respect from chlamydia-positive women who were free of infectious complications. These results suggest that C. trachomatis may be an etiologic agent in postabortal salpingitis and probably also in endometritis. Serum antibodies seemed to offer some protection against salpingitis in chlamydia-positive cases, whereas local antibodies did not.