P–445 Successful live birth after repeated high-dose radiotherapy to the uterus

Abstract

Study question It has been established that radiotherapy can increase the risk of adverse pregnancy outcomes. However, there is currently no consensus on the effective sterilizing dose for adulthood uterine radiotherapy. Summary answer Uterine fertility preservation methods should be guided by the age of the patient receiving radiotherapy and the actual dose of radiation exposure to the uterus. What is known already Many experts have suggested that a high dose of radiation to the uterus is a reason to counsel patients against future pregnancy. There are major limitations to the current literature regarding off-target radiation damage to the uterus. One study reported a relative risk of 9.1 for stillbirth and neonatal death after 10 Gy doses. Study design, size, duration Case report and review of the literature before December 2020 Participants/materials, setting, methods A case report of a 36-year-old female with three cancers and received repeated high-dose radiotherapy of 66 Gy and 50 Gy to the pelvis. We used a dose-volume histogram, the most widely used tool to calculate the radiation distribution within a volume of interest of the patient during radiotherapy. We determined that her uterus may have received the highest uterine radiation dosage for full-term live birth in current literature. Main results and the role of chance Due to iatrogenic ovarian failure, she could only use donor eggs. After endometrium preparation for 18 days, the endometrium reached 8.7 mm with a triple-line appearance. We transferred two cleavage-staged embryos and one of them implanted successfully. The course of the pregnancy was uneventful. Finally, the patient gave birth to a healthy baby via Cesarean section at 38 5/7 weeks of gestation. Limitations, reasons for caution It should be noted that the success of our case may not apply to all patients with cancer after they have received RT. We should inform patients about the increased risk of preterm birth, low birth weight infants, uterine rupture, and neonatal death. Wider implications of the findings: The patient’s age and the dose of RT exposure to the uterus are important factors for the prognosis of a future pregnancy. More well-designed studies will be needed to allow future standard guidelines for uterine fertility preservation. Trial registration number TMU-JIRB N20204149