Recurrent Molar Pregnancy

Abstract

Molar pregnancy is one form of gestational trophoblastic disease as a result of abnormal fertilisation and gametogenesis, characterised by hydropic swelling of the placental villi, hyperplasia of villous trophoblast and absent, or abnormal, faetal development. It is potentially a malignant pregnancy condition, broadly grouped under gestational trophoblastic disease (GTD). The commonest molar pregnancy is complete hydatidiform mole (CHM) and the next common is partial hydatidiform mole (PHM). The malignant form of GTD is otherwise called gestational trophoblastic neoplasia (GTN) which encompasses: Invasive mole (IM), Choriocarcinoma (CCA), Placental site trophoblastic tumour (PSTT) and Epitheloid trophoblastic tumour (ETT). More than 80% of molar pregnancies are cured with usual suction and evacuation with regular follow-up with clinical and β-hCG estimation. About 15–20% of CHM and 3–5% of PHM will require chemotherapy depending upon the WHO score for GTN with normal pregnancy outcome thereafter. However, it is typical that once molar pregnancy there is a high risk of molar events in subsequent pregnancy. By definition, recurrent hydatidiform mole is characterised by the occurrence of at least two abnormal pregnancies that have resulted in hydatidiform mole.