Pregnancy-induced hypertension (PIH), especially when complicated with pre-eclampsia (PE), could be a life-threatening complication of pregnancy. Pre-eclampsia is one of the leading causes of perinatal morbidity and mortality in women. Pre-eclampsia is mainly characterized by hypertension and kidney damage with proteinuria. Abnormal placentation and altered structure of the placental barrier are believed to participate in the pathogenesis of pregnancy-induced hypertension, leading to PE. In the current study, we aimed to analyze the immunohistochemical expression pattern of E-cadherin and p120, two markers of epithelial–mesenchymal transition, in placental samples derived from a group of 55 patients with pregnancy-induced hypertension, including pre-eclampsia and 37 healthy pregnant controls. The results were correlated with the presence of an obtained early uterine artery flow notching during diastole on Doppler ultrasound. We observed a higher frequency of discontinuous E-cadherin staining in the basement membrane of syncytiotrophoblast in patients with PIH/PE compared to controls (p < 0.001, Fisher’s exact test). Moreover, the loss of continuity of E-cadherin expression correlated with the presence of a bilateral early diastolic notch on Doppler ultrasound (p < 0.001, Fisher’s exact test) and the presence of proteinuria (p = 0.013, Fisher’s exact test). These findings suggest that E-cadherin contributes to the integrity of the placental barrier, and its loss could be an immunohistochemical marker of PE.