Mast cells in the normal uterus and in dysfunctional uterine bleeding.

Mast cells in the human uterus were examined following fixation in 10% formalin and staining with Azure B. Mast cells were present in all parts of the corpus uteri. Cyclical changes were observed by light microscopy for mast cell numbers/mm2 in the functional endometrium, basal endometrium and the endometrial/myometrial border throughout the menstrual cycle. No significant differences were found for mast cell numbers in the menstrual, proliferative or secretory phases of the menstrual cycle in dysfunctional uterine bleeding (DUB). No correlation was found between mast cell numbers in the uterine wall in the secretory phase of the menstrual cycle and average menstrual blood loss for patients with DUB.