Abstract: The present Application provides in one aspect a method of diagnosing a menstrual cycle event in a subject (e.g., a WOI), comprising detecting in a biological sample a gene signature for one or more endometrial cell types (e.g., unciliated epithelial cells). The present Application in another aspect provides a method comprising determining a gene expression profile in each of a plurality of endometrial cells, wherein said endometrial cells are: (a) in an endometrial sample obtained from a subject, and (b) unciliated epithelial cells.