Infectious agents in tissues from spontaneous abortions in the first trimester of pregnancy.

Some evidence suggests that intrauterine infection plays a major role in the pathogenesis of early pregnancy loss, but the implication and prevalence of microrganisms in the aetiology of spontaneous abortion during the first trimester of pregnancy has not yet been well established. In this study, we analysed the tissues relative to the product of conception from abortions during the first trimester (51 spontaneous abortions and 56 voluntary pregnancy interruptions) in women attending the Gynecological Sciences Perinatology and Puericulture Department of "Policlinico Umberto I". Specimens were investigated by cultural methods for the presence of yeasts, gram positive, gram negative bacteria, and genital mycoplasma. By molecular diagnostic procedures, DNA sequences of Chlamydia trachomatis, herpes simplex viruses, adenovirus, human papillomaviruses and human polyomaviruses BK and JC were searched. None of these agents could be found in voluntary pregnancy interruption samples, with the exception of 3.6% of specimens positive for adenovirus, whereas spontaneous abortion tissues were positive for at least one microrganism by 31.5%. Data analysis showed the occurrence of both monomicrobial and polymicrobial infections.