The present in vitro study was focused on the differences in expression and activity of calcium release-activated calcium (CRAC) channels of human term-pregnant and non-pregnant myometrium. The expression of Orai1 protein, as a functional subunit of CRAC channel, was significantly higher than in non-pregnant myometrium. Lower Orai1 protein expression did not influence the amplitude of contractile response of term-pregnant myometrium, but higher Orai1 expression observed in non-pregnant myometrium was related to the different influence of CRAC blocker on contraction frequency.