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Lipiodol (Ethiodized Oil) & Infant Thyroid Dysfunction

    Basic Details
    Status
    Complete
    Last Updated
    Wednesday, July 23, 2025
    Original Posting Date
    Health Outcome(s)
    infant thyroid dysfunction
    Purpose
    Drug and Outcome Analysis
    Meets requirements of FD&C Act Sec 505(o) prior to requiring a PMR
    No
    Study Summary

    The U.S. Food and Drug Administration (FDA) initiated this study to assess the feasibility of using mother-infant linked data in the Sentinel System to evaluate the association between in utero exposure to Lipiodol (ethiodized oil) used in hysterosalpingography (HSG) procedures and the development of neonatal thyroid dysfunction, in comparison to in utero exposure to non-oil based iodine agents used for HSG. The Sentinel study was prompted by a study in Japan published in 2015 that reported the frequency of infantile hypothyroidism after exposure to ethiodized oil was higher in their study population (2.4%), compared to 0.7% for congenital hypothyroidism in the Japanese population.

    This Sentinel study aimed to monitor Lipiodol use in HSG and infant thyroid dysfunction in the United States. An initial query evaluated the utilization of Lipiodol and non-oil based iodine agents. A very low number of HSG patients with exposure to either Lipiodol or to non-oil agents was observed in relation to the total number of HSG patients. This observation indicated the under-capture of exposure to these contrast agents during a HSG procedure. Therefore, the Active Risk Identification and Analysis (ARIA) System was found to be insufficient to conduct a full study.