There is a huge controversy in the scientific community regarding the clinical significance of these factors in the pathogenesis of recurrent miscarriages. My personal experience leads me to the conclusion that chronic endometritis certainly leads to miscarriages and that the immune mechanisms are certainly involved in this phenomenon. The difficulty lies in the identification of the underlying pathogenic factor and its specialised treatment. The immune mechanisms are a labyrinthine and chronic endometritis is very easily hidden by the endometrial cell cultures and biopsies and vaginal swab cultures. Personally, when I have a strong clinical suspicion of endometritis, I perform a hysteroscopy, looking for clinical signs, proceed to endometrial biopsy and treat my patients with the appropriate antibiotic combination. There are many cases of patients that I remember that have benefited from this approach.