Unexplained Total Fertilization Failure after Intracytoplasmic Sperm Injection Cycles: A Case-Control Study on Predictive Factors and Retreatment Prognosis.

Background: The aim of our study was to detect the rate of unexplained total fertilization failure (TFF) after intracytoplasmic sperm injection (ICSI) and identify its risk factors and retreatment prognosis.

Materials And Methods: In this retrospective case-control study, we searched the computerized database of the Royan Institute (Tehran, Iran) from March 2015 to March 2019 and retrieved all cases diagnosed with TFF after ICSI. TFF cases that did not have any recognized risk factors were classified as unexplained (subgroup A).