Background: The ubiquitous Bacillus cereus bacterium can cause numerous clinical diseases, from transient bacteremia to life-threatening systemic infections. Studies have indicated that non-anthracis Bacillus species, such as Bacillus cereus, may be clinically significant concerning placental infection, and the resulting outcomes for the fetus.

Case presentation: We report a woman who developed an acute intrauterine infection following mid-trimester genetic amniocentesis. Twenty-seven hours after the procedure, the mother experienced septic shock, disseminated intravascular coagulation (DIC), and fetal death. Microbiology cultures of placental and fetal swab samples taken during hysterotomy and maternal blood samples taken upon admission revealed the growth of Bacillus cereus. The placental pathological examination revealed a large number of microorganisms in the fetal vessels of the chorionic villi, along with signs of acute villitis and chorioamnionitis.

Conclusion: This case study highlights the significance of placental intravascular organisms in acute intrauterine infection caused by Bacillus cereus. It also emphasizes the importance of histological analysis, which offers crucial details about the time of onset of the infection and the causative agents and informs present and future obstetric care of these patients, and the significance of placental intravascular organisms in acute intrauterine infection caused by Bacillus cereus.

Keywords: Bacillus cereus; amniocentesis; chorioamnionitis; fetal intravascular organisms; sepsis; villitis.

© 2025 Xu et al.