The effect of tetracycline treatment on chlamydial salpingitis and subsequent fertility in the mouse.

The effect of tetracycline X HCl, administered for 14 days starting before or after intraovarian bursa inoculation of the mouse pneumonitis biovar of Chlamydia trachomatis, was examined in mice. Mice that received no antibiotic developed acute salpingitis and subsequent hydrosalpinx. Only one of ten mated mice at 42-51 days after inoculation showed a normal, bilateral pregnancy. Initiation of tetracycline treatment two days prior to inoculation completely prevented the pathology associated with tubal chlamydial infection and fertility was as high (eight of ten) as in mice inoculated with sterile tissue culture supernate (eight of 11). Initiation of treatment one week after inoculation prevented permanent tubal damage (two of 20 vs. 12 of 20; P = .001) and infertility (bilateral pregnancies, six of ten vs. one of ten; P = .027) in some, but not all, infected mice. Therapy began two weeks after inoculation resulted in a marginal improvement in the frequency of apparently normal oviducts (16 of 24 vs. eight of 20; P = .053) but not in fertility (bilateral pregnancies, four of 12 vs. one of ten; P = 0.19). This model may be of value in studies of the treatment of upper genital tract infection with C. trachomatis.