Spontaneous abortion--an infectious aetiology?

The role of Chlamydia trachomatis, genital mycoplasmas, Campylobacter spp. and other aerobic and anaerobic bacteria in the aetiology of spontaneous abortion was investigated prospectively in 241 pregnant women at a community hospital. Sixteen women who had threatened abortions were a little younger, of lower social class and had had more previous spontaneous abortions than the 76 women who aborted or the 149 women whose pregnancies were not complicated in the early stages by haemorrhage. The demographic characteristics of the latter two groups of women were similar. C. trachomatis was isolated from the cervix of only one woman and she had no genital-tract bleeding at any stage in her pregnancy. Mycoplasma hominis was isolated most often from the women who had threatened abortions but otherwise the prevalence of the other various micro-organisms was similar in women who had spontaneous abortions, threatened abortions, and in those who had pregnancies uncomplicated by vaginal bleeding. It was clear, therefore, that C. trachomatis played no role in the aetiology of spontaneous abortion in the population studied and there was no suggestion that any of the other micro-organisms were involved either.