Two women with preterm labor and intraamniotic infection with Listeria Monocytogenes are presented. In both patients, the prenatal diagnosis of Listeriosis was made by transabdominal amniocentesis. The immediate prominent observation was meconium staining of the amniotic fluid. We propose that an amniocentesis should be performed in women with premature labor and fever. If the amniotic fluid is meconium stained and the Gram stain examination reveals Gram positive rods, Listeria Monocytogenes should be suspected and the patient should be treated accordingly until the culture results are obtained.