A 34-year-old woman, who had a history of five spontaneous losses and failures of two McDonald purse-string cerclages, underwent a transabdominal cervico-isthmic cerclage (TCC). She became pregnant 17 months after TCC. At 35 weeks of gestation, she was admitted to our hospital due to preterm labor and delivered a healthy female baby (2270 g) by cesarean section. After delivery of the newborn infant, we found a migration of about one third of the cerclage band into the endocervical canal. Two years later, she had one further pregnancy, reached 33 weeks of gestation, and delivered a 1450 g male baby by cesarean section due to a preterm labor without any signs of infection. Although it could have been a case of pure coincidence, we take a chance to speculate that the migration of the cerclage band into the endocervical canal might have been the reason for the preterm labor, and it must have been removed at her first cesarean section and replaced by a new cerclage band for her next pregnancy.