Practical guidelines of the EOTTD for pathological and genetic diagnosis of hydatidiform moles

New guidelines from the Pathology and Genetics Working Party of the European Organisation for Treatment of Trophoblastic Diseases that describe the pathological criteria and ancillary techniques that can be used in the differential diagnosis of hydatidiform moles.


Brendan Fitzgerald, Caroline Joyce

Journal Name
Virchows Archiv
Journal Article
Molar pregnancy / Gestational Trophoblastic Disease

Biomarkers for Gestational Trophoblastic Disease

Full Citation

Bartosch C, Nadal A, Braga AC, Salerno A, Rougemont A-L, Van Rompuy A-S, Fitzgerald B, Joyce C, Allias F, Maher GJ, Turowski G, Tille J-C, Drak Alsibai K, Van de Vijver K, McMahon L, Sunde L, Pyzlak M, Downey P, Wessman S, Patrier S, Kaur B, Fisher R. Practical guidelines of the EOTTD for pathological and genetic diagnosis of hydatidiform moles. Virchows Arch. 2024;484(3):401-422.

Link to Publication


A small percentage of miscarried pregnancies may have abnormal placental tissue that is described as a “Hydatidiform Mole”, sometimes described as a “molar pregnancy”. This molar placental tissue carries a risk of persisting within the womb or in rare instances becoming malignant in which case chemotherapy may be required. In miscarriages from early stages of pregnancy, these molar pregnancies can be difficult for the pathologist to diagnose and they may need to use special techniques or involve geneticist colleagues. This paper provides guidelines for the diagnosis of molar pregnancies, agreed by an expert European Group, that pathologists and geneticists can use as a diagnostic guide. With accurate diagnoses, patients can ultimately be managed most appropriately.

Pregnancy Loss Research Group

Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Fifth Floor, Cork University Maternity Hospital, Wilton, Cork, T12 YE02, Ireland,