The phenotype of human triploidy

Triploid infants are born prematurely and usually live less than one day. The triploidy syndrome is characterized by general dysmaturity and the following features: muscular hypotonia; large placenta with frequent hydatidiform changes; large posterior fontanel; low-set dysmorphic auricles; hypertelorism; microphthalmia and colobomata; cutaneous syndactyly of fingers three and four; simian crease; maldeveloped external genitalia; hypospadias; cryptorchidism and Leydigian cell hyperplasia of the testes in XXY males and hypoplastic adrenals.