Hydatidiform moles are abnormal conceptions, which
occur in about one in 500 –1000 pregnancies
1
. Pathological and cytogenetic studies have demonstrated that
molar pregnancies may be either of two distinct subtypes,
complete and partial hydatidiform mole. Complete moles
are usually diploid and androgenetic, pathologically demonstrating minimal embryonal development with hydropic
chorionic villi and trophoblastic hyperplasia, while partial
moles are usually paternally derived triploid conceptions
in which embryonal development occurs in association
with trophoblastic hyperplasia
2,3
. Presentation is usually
with first or second trimester vaginal bleeding, but more
recently, diagnosis may be made at the time of routine
early pregnancy ultrasound scanning
4
.