Horse Side Vet Guide ®

Equine Health Resource

Uterine Cytology



Uterine cytology is a common diagnostic test that provides information about the health of a mare’s uterus and the current stage of their heat cycle. It involves the examination of uterine lining cells that have been collected on a swab. The laboratory work is typically done in an equine hospital, so there is little delay in receiving the results. It is an important complementary test to the uterine culture.

This procedure involves sterile technique, wherein a cotton swab or cytology brush is passed through the cervix and into the uterus. It is rolled around to collect cells and removed. The swab is carefully smeared onto a slide, stained and examined under the microscope. Uterine lining cells and inflammatory cells are typically seen. The ratios and characteristics of those cells indicates different stages and health of the uterine environment.


This test is convenient and the results are almost immediately available. Along with the uterine culture, the cytology results are helpful in diagnosing uterine infection and developing an appropriate treatment plan.


Only the very surface cells are sampled using this technique. In contrast, the results of a uterine biopsy provide a more detailed account of uterine health. Poor technique of smearing the cells on a slide can destroy the cells, making the slide non-diagnostic. It takes practice to make useable slides.

Helpful Outside ResourcesCredible Equine Health Information on the Internet


  • Does this diagnostic add anything beyond uterine culture?
  • Why do we need to do this and perform a culture?
  • Why not just do a uterine biopsy?
  • Author: Doug Thal DVM Dipl. ABVP


    We're not around right now. But you can send us an email and we'll get back to you, asap.