IntroductionMorbidly adherent placenta is a clinical condition of which prevalance is steadily increasing. It is described as the invasion of the placenta into the uterine wall through the myometrium and beyond. Vascular cell adhesion molecule-1 is a calcium independent transmembrane glycoprotein. Several studies have shown that vascular cell adhesion molecule-1 increases invasion in tumor cells. In our study we investigated the expression of vascular cell adhesion molecule-1 which has been shown to increase invasion in various tumors in morbidly adherent placenta cases. Material and methodThis is a prospective case–control study. Eighty-four patients who were diagnosed with morbidly adherent placenta and 96 patients without any risk factors as a control group were included in the study. Vascular cell adhesion molecule-1 staining was examined by immune-histochemical staining in placental samples. ResultsThe patients included in the study were similar in terms of demographic characteristics. Of the 84 patients in the morbidly adherent placenta group, 65 (74.7%) showed positive staining. This number was 39 (40.6%) in the control group. Staining in morbidly adherent placenta group was statistically significantly higher (p<0.05). DiscussionThe etiology of morbidly adherent placenta is still a clinically unknown condition. This study is the first study on this field in the literature. In our study, we showed that vascular cell adhesion molecule-1 expression increased in morbidly adherent placenta group. Although the entire pathogenesis is not explained this can be considered as a step for understanding this subject.