Objective — to reveal the morphological and immunohistochemical features of placental tissue in placentation abnormalities. Subject and methods. Forty-two birth records and protocols for morphopathological study of histological material from patients were retrospectively analyzed. Group 1 included 16 women diagnosed with placental ingrowth (placenta accreta, placenta increta), who had a hysterectomy during delivery; Group 2 consisted of 14 women with firm placentation (placenta adhaerens), who had also hysterectomy, and Group 3 (a comparison group) comprised 12 women who had delivered a baby at 36—40 weeks’ gestation without abnormal placentation. Results. Women with morphologically confirmed invasion of chorionic villi into the myometrium (Group 1) were recorded to have a lower bcl-2 expression in decidual tissue and a higher p53 expression by trophoblast cells, which may be evidence that the regulation of apoptotic mechanisms is impaired in decidual tissue and trophoblast. The stroma of placental tissue from women with abnormal placentation showed a low expression of LIFR signaling molecules, whereas most patients of this group had a dominant expression of LIF in the cytoplasm of invasive trophoblast and decidual tissue; as well as the expression of CD62L (L-selectin) was increased in the stroma of villi. Conclusion. The findings suggest that the shift in producing the markers of trophoblast invasion and apoptosis play a significant role in placental ingrowth (placenta accreta, placenta increta), which necessitates further investigations.