The registry and the biorepository have prospective and retrospective components.~The prospective component of the registry and the biorepository focuses on the collection of demographic, clinical, and biological material of patients prospectively identified as having the AFE syndrome, including the collection of future samples from survivors and related individuals. Typically, healthcare providers, family members of an affected patient, or patients themselves contact the AFE Foundation. The AFE Foundation provides information about the natural history of the syndrome and its outcomes and invites patients to participate in the registry and biorepository. The AFE Foundation obtains informed consent from patients or next of kin for enrollment in this observational study. There is no randomization or placebo group for this registry as it is exclusively an observational study. If maternal specimens are available pre- and post-event during the hospital admission for delivery, these samples will also be collected from each patient. The only group assignment will be the subjects with a diagnosis of AFE and the subjects' family members including the partner(s) and child (children).~The retrospective component of the registry consists of obtaining clinical information and biological material from patients who have been previously affected by the AFE syndrome. This objective includes obtaining medical records, patient-provided information, pathology reports, autopsy reports, and tissue blocks. Biological samples can also be obtained from survivors and relatives to determine whether there are biomarkers in previously affected patients or whether biomarkers can be elicited from the stimulation of peripheral blood cells. In addition to collecting data and specimens from the patients that are consented and enrolled through the registry, a query of all maternal deaths within 24 hours of birth between 1/2012 to 1/2023 will be performed at the Hermann Hospital system to identify if any of these deaths occurred secondary to AFE. The investigators intend to perform a detailed chart review and collect otherwise discarded tissue if available from the respective hospital to perform special immunohistochemistry staining among women who underwent autopsy.
To establish a clinical registry of suspected cases of AFE. The existing registry will be migrated to a new platform,