Differences in current clinical features of diploid and triploid hydatidiform mole

To describe and compare the current clinical features of diploid and triploid molar pregnancy and to evaluate whether the presenting clinical features can predict the ploidy of a molar pregnancy.

A retrospective study of the clinical features and ploidy of hydatidiform moles.

The Departments of Clinical Genetics and Pathology, Aarhus University Hospital and 13 gynaecological wards, Jutland, Denmark.

A total of 259 women with molar pregnancy diagnosed between April 1986 and June 2003.

A review of medical records of consecutively collected, clinically suspected cases of molar pregnancy was performed. The molar ploidy was determined by karyotyping, flow cytometry, and/or analysis of polymorphic DNA markers.

Maternal characteristics, presenting symptoms, initial human chorionic gonadotrophin (hCG), and molar ploidy.

In a multiple logistic regression model, initial hCG of > or = 100,000 iu/l (P < 0.001), first-trimester gestational age (P < 0.001), vaginal bleeding (P < 0.001), and maternal age of > or = 40 years (P = 0.03) were independent predictors of diploid mole. Women with excessive uterine size more frequently had a diploid than a triploid mole (P < 0.001). Fifty-four percent of the women with triploid mole and 27% of the women with diploid mole were diagnosed before onset of symptoms (P < 0.001).

The current clinical features of diploid mole are different from those of triploid mole. The presenting clinical profile of a molar pregnancy may be used as an early predictor of the molar ploidy and thus of the prognosis.