Second-trimester abortion caused by Capnocytophaga sputigena: case report.

Intra-amniotic infection is often the cause of a second-trimester abortion. The bacterial species involved include bacteria with low pathogenicity like Ureaplasma urealyticum and various Mycoplasma species. In this case we describe an intra-amniotic infection caused by Capnocytophaga sputigena, often found in the normal bacterial flora of the oral cavity, but not in the vagina. Oral sex during pregnancy was the most probable source of the infection. The aborted fetus showed signs of pneumonia upon histologic examination. The bacterial species was identified using broad-spectrum 16S rDNA polymerase chain reaction (PCR) directly from the amniotic fluid and after bacterial culture. Amniotic fluid glucose was below detection level, confirming the presence of an intra-amniotic infection.