Link Between Subchorionic Hematoma Post Chorionic Villus Sampling and Rare Fannyhessea vaginae Bacteraemia and Implications for Pregnancy Loss: A Case Report and Literature Review

Background and Clinical Significance: Fannyhessea vaginae (formerly Atopobium vaginae) is an anaerobic, Gram-positive coccus associated with bacterial vaginosis and, rarely, invasive infection. Its role in adverse pregnancy outcomes, particularly following invasive prenatal procedures, remains poorly understood. Case Presentation: We report a 32-year-old woman, gravida 3, para 2, who underwent transabdominal chorionic villus sampling (CVS) at 12 + 6 weeks gestation for prenatal diagnosis of ABCA3 deficiency, following the death of a previous child from the same condition. She developed a persistent subchorionic haematoma with recurrent vaginal bleeding, followed by rising inflammatory markers, malodorous amniotic fluid and a late miscarriage with placental abruption at 20 + 6 weeks. Blood cultures taken at the onset of labour grew F. vaginae, identified after discharge, prompting readmission for intravenous antibiotics. She subsequently underwent evacuation of retained products of conception. Placental histopathology confirmed abruption with only early inflammatory changes, and vaginal and placental swabs did not isolate the organism. To our knowledge, this is the third reported case of F. vaginae bacteraemia associated with pregnancy loss following CVS, and the first following a transabdominal approach. We propose that the persistent subchorionic haematoma may have facilitated ascending infection from the lower genital tract, although a causal relationship could not be established. Conclusions: This case highlights F. vaginae as an under-recognised but potentially clinically significant pathogen capable of causing septic miscarriage and underlines the need for raised clinical suspicion and further research into its role in pregnancy.