During implantation, human trophoblastic cells have to proliferate, migrate and invade pregnant uterus. A natural product of cruciferous vegetables, 3,3'-diindolylmethane (DIM), is known to induce some stress response genes (such as glucose-regulated protein 78 kDa (GRP78)) and to have anti-invasive and pro-apoptotic effects on tumor cells. Therefore, we have investigated the potential effect of DIM on invasive extravillous cytotrophoblasts (evCTBs) cells.