KISS1R and placenta praevia: As trophoblasts begin to invade, plasma KISS1 concentrations during the peri-implantation period may reflect early developmental events associated with pregnancy outcome.[9] In humans, KISS1 plasma concentration increases markedly during pregnancy.[10] The possible effects of KISS1 and kisspeptin receptor (KISS1R) on intracellular skeletal organization, cell migration and collagenase activity have been reported in previous studies.[11,12] The migration of placental cells and intercellular collagenase activity may play an important role in patients who develop placenta previa.