Genital infections with Chlamydia trachomatis in women attending an antenatal clinic.

Cervical swabs for isolation of C. trachomatis and serum for anti-chlamydial antibodies were taken from 252 pregnant women on their first visit to an urban antenatal clinic. Chlamydial infection was found in 18 (7%) women, and antibody at titres greater than 1/32 in 48 (19%); of the 18 infected women only 10 (56%) showed antibody. The likelihood of infection could not have been predicted by urogenital symptoms, the social or medical history or serology. Hypertrophic cervical ectopy and mucopus were significantly more common in infected than in uninfected women but underestimate the true rate of infection. The consorts of 10 infected women had signs of non-gonococcal urethritis but were asymptomatic; C. trachomatis was isolated from the urethra of one man. The indications for routine screening of antenatal patients for chlamydial infections is discussed.