© 2014 John Wiley & Sons Ltd. Aims: The significance and pathogenesis of irregular or asynchronous maturation within endometrial glands remains uncertain. The aim of this study was to investigate differences in epithelial hormone receptor immunoreactivity and stromal cell calretinin, CD34 and p16 expression in morphologically normal secretory endometrium and in asynchronous (non-secretory) endometrial glands (AEGs). Methods and results: Nineteen consecutive endometrial specimens showing AEGs were examined. The mean age of the patients was 42.8 years, and the most common presenting symptom was menorrhagia. Immunohistological expression of oestrogen receptor (ER) α, of ERβ and of progesterone receptor (PR) were compared in normal secretory glands and in AEGs. Stromal cell expression of calretinin, CD34 and p16 was also investigated. In contrast to normal secretory glands, the epithelial cells lining AEGs were usually ERα/PR-positive and showed significantly increased ERβ expression. Altered calretinin and CD34 expression within functional layer stromal cells was seen in five and two cases, respectively, but there were no differences in stromal cell immunoreactivity around AEGs. Conclusions: The most common clinical symptom associated with AEGs in this study was menorrhagia. Aberrant hormone receptor expression in AEGs suggests a localized, possibly clonal, defect in epithelial maturation. There were no immunophenotypic changes to suggest that AEGs are related to a primary endometrial stromal deficiency.