Histamine isolated from many different tissues, acts via three types of histamine receptors: H1, H2 and H3. In peripheral tissues histamine is mainly stored in mast cells (MC). Presence of mast cells was proved also in mammals' uteri. In human uterus the majority of mast cells are located close to smooth muscle cells. It might indicate that MC plays a role in tissue remodelling during the menstrual cycle. The quantity and activity of mast cells is in connection with hormonal status of the organism. Although there are some differences, human uterine mast cells are similar to the mast cells isolated from other tissues. It is suggested that histamine is important for normal ovulation, blastocyst implantation, placental blood flow regulation, lactation and contractile activity of uterus. Histamine may also play a role in pathological processes such as pre-eclampsia or preterm delivery. The participation of mast cells and histamine in blastocyst implantation is very controversial. In W/Wv mice (without mast cells) normal implantation was observed. It denies the main role of mast cells in this process but dos not exclude histamine action. In mice the major source of histamine are uterine epithelial cells during early pregnancy. The influence of cytokines on blastocyst implantation and the role of histamine in cytokines release from the uterine mast cells are also very unclear.