A complete hydatidiform mole (CHM) is a type of molar pregnancy and falls at the benign end of the spectrum of gestational trophoblastic disease. Epidemiology ...×ArticlesLogInCasesSignUpCoursesQuizBlogDonateAbout×MenuSearchADVERTISEMENT:Radiopaediaisfreethankstooursupportersandadvertisers.BecomeaGoldSupporterandseenoads.ArticlesCasesCoursesLogInLoginSignup{"url":"/signup-modal-props.json?lang=us\u0026email="}ArticlesCasesCoursesQuizAboutBlogGoad-freeSearchCompletehydatidiformmoleDrMohamedSaberandRadswiki◉etal.Acompletehydatidiformmole(CHM)isatypeofmolarpregnancyandfallsatthebenignendofthespectrumofgestationaltrophoblasticdisease. Onthispage:Article:EpidemiologyPathologyRadiographicfeaturesTreatmentandprognosisSeealsoRelatedarticlesReferencesImages:CasesandfiguresImagingdifferentialdiagnosisEpidemiologyAcompletehydatidiformmoleisthecommonesttypeofgestationaltrophoblasticdisease.PathologyCompletemolesarecharacterizedbytheabsenceofafetusorfetalparts(i.e.noembryonictissues).Thereisanon-invasive,diffuseswellingofchorionicvilli.ChromosomalcompositionApproximately90%ofcompletehydatidiformmoleshavea46XXdiploidchromosomalpatternwith~10%havinga46XYcomposition.Allthechromosomesarederivedfromthesperm,suggestingfertilisationofasingleeggthathaslostitschromosomes.MarkersSerumbetaHCGlevelsaremarkedlyelevated,outofproportiontothepregnancy. RadiographicfeaturesUltrasoundenlargeduterusmaybeseenasanintrauterinemasswithcysticspaceswithoutanyassociatedfetalpartsthemultiplecysticstructuresclassicallygivea"snowstorm"or"bunchofgrapes"typeappearance.maybedifficulttodiagnoseinthefirsttrimester6mayappearsimilartoanormalpregnancyorasanemptygestationalsac<50%arediagnosedinthefirsttrimesterbilateralthecaluteincystsmayalsobeseenonultrasoundcolorDopplerinterrogationmayshowhighvelocitywithalowimpedanceflowCTCTevaluationisnotusuallyperformedduetoitslowresolutionfortheuterineassessment. CTmayshowanenlargeduteruswithareasoflowattenuation,orhypoattenuatingfocisurroundedbyhighlyenhancedareasinthemyometr