Vaginal Cytology: Introduction and Index

The vaginal epithelium is responsive to sex steroids, particularly estrogen, and undergoes predictable changes through the cycle in response to changes in blood concentrations of ovarian hormones. Rising levels of estrogen cause the vaginal epithelium to become "cornified" - the surface cells become large and flattened, with small or absent nuclei.

In essence, vaginal cytology is a type of endocrine assay. Tracking changes in the morphology of desquamated vaginal epithelial cells provides a convenient means of assaying changes in estrogen levels.

The technique is used widely in managing canine breeding programs, which is the focus of this section, but also has utility in evaluating reproductive function in several other species, including cats (if you don't mind losing a little blood) and rats.

Core information on canine vaginal cytology is presented in the following topics:

Author: R. Bowen
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