Hysteroscopy picture retained products of conceptionThe concept of placental polyp (retained products of conception) refers to the presence of placental, or deciduous fetal remains, retained into the uterine cavity after an abortion, vaginal delivery or a cesarean section. It is estimated that occurs in about 1% of all births at term and likely to have a higher incidence in preterm births and abortions. Two theories have been proposed to explain the pathogenesis of this condition. One theory proposed by Eastman and Hellman suggest that the presence of retained products is probably due to a certain degree of placenta accreta. A second theory described by Ranney explains the retained products of conception due to differences in thickness, tone and contractility of the myometrium after injury during the current pregnancy.