Table 1 Twenty epithelial characteristics and their descriptions used to evaluate uterine biopsies using SEM

1. Epithelial abundance – the amount of epithelium found within the sample

11. Cell separation – at times cells are observed to be separate rather than tightly clustered together

2. Tissue heterogeneity – the variability of tissue surfaces within the sample

12. Denuded apices – cell surfaces are devoid of surface modifications such as microvilli, cilia (excluding uterdomes)

3. Cell heterogeneitiy – the variability of the appearance of the cell types within each field

13. Flattened cells – degree to which cells display a flattened topography

4. Gland abundance – the relative number of glands observed within each field

14. Deflated cells – whether cell apices appear to have collapsed or withered

5. Gland opening – the types of gland opening, whether wide, raised, narrow

15. Apical protrusion – the degree to which the cell surface protrudes into the lumen of the uterus

6. Cilia groups – the relative number of ciliated cells clustered together

16. Uterodomes – shape (see Uterodome Assessment)

7. Single cilium – presence of these indicate a senescent or atrophying epithelium

17. Uterodomes – abundance (see Uterodome Assessment)

8. Microvilli height – the relative length of microvilli, from short and blebbed to long

18. Cell borders -may be obvious or deeply recessed between cells

9. Microvilli density – relative number of microvilli per cell, from few to many

19. Secretion – the presence of secretory product within the field or on cell surfaces

10. Apical membrane defects – include observation of porosity and degeneration

20. Plicae – are microvillous folds or ridges on the cell surfaces