Hereditary thrombophilia in a family with three independent protein S and C mutations. A cause of adverse perinatal outcome

A non-related couple with two independent protein S and a protein C mutation had two of their three children suffering from severe thrombosis resulting in neonatal death of the firstborn. With prenatal testing an accurate prediction of phenotype was possible for the second child but the third infant was more severely affected than had been predicted from the genotype.