A CASE OF PARTIAL MOLE ASSOCIATED WITH TRISOMY-13

The majority of second-trimester partial moles are found in associatio n with triploidy. Rarely are they associated with tetraploidy or other aneuploidies and, to our knowledge, this is the first reported case o f the prenatal diagnosis of partial mole in a pregnancy presenting wit h trisomy. The patient was referred at 21 weeks of gestation after a r outine ultrasound examination had shown fetal and placental features s uggesting a partial mole triploidy. Owing to the severe structural mal formations and poor prognosis, the parents requested termination. Pren atal and postnatal cytogenetic investigations demonstrated an addition al chromosome 13. Histopathological examination of the placenta showed focal areas of villous edema bur no evidence of trophoblastic dysplas ia. The maternal serum human chorionic gonadotropin level was within t he normal range at all times. This case shows that trisomy can resembl e a triploid partial mole in utero without the potential long-term ris k to the mother of persisting trophoblastic disease, as villous molar changes can obviously develop without trophoblastic dysplasia.