Prenatal diagnosis of triploidy associated with holoprosencephaly: a case report and review of the literature.

We sought to identify risk factors of prenatal presentation of holoprosencephaly associated with triploidy. A case report is presented with review of the literature performed using the PubMed database. The latest search was done in June 2008. Literature review showed 11 reports with a total of 15 cases of holoprosencephaly associated with triploidy. The mean maternal age at diagnosis was 27 +/- 4.9 years, and the mean gestational age at diagnosis was 13.6 +/- 3.3 weeks. Triploidy was mainly associated with the alobar type of holoprosencephaly. Only 3 (20%) cases had associated placental abnormalities. In all cases, the pregnancy was terminated. The latest gestational age at which termination was performed was 23 weeks. Facial abnormalities were the most common associated feature (66.6%). The association of triploidy with holoprosencephaly is very rare. This association does not seem to be related to maternal age. It is mainly associated with alobar holoprosencephaly. Diagnosis is possible during the first trimester. Fetuses can survive up to the third trimester.