Vaginal Cytology

Vaginal cytology is a microscopic examination of cells collected from the vaginal epithelium, used in veterinary medicine to identify the stage of the estrous cycle in female mammals. Because the vaginal epithelium changes in response to shifting sex hormone levels, examining a stained vaginal smear lets a veterinarian tell where a female animal, most commonly a female dog, stands within her estrous cycle. A normal smear may show lactational, navicular, endocervical, endometrial and trophoblastic cells along with leucocytes, and the procedure is carried out with a vaginal speculum, cotton-tipped applicators, frosted microscope slides, a commercial Romanowsky stain and a light microscope.