Second trimester antenatal diagnosis in rare coagulation factor deficiencies

Prenatal diagnosis is sought after for those genetic disorders, whose management is not satisfactory either because of the outcome or owing to extreme cost involved in the management of the patients affected by a specific disorder. Severe hemophilia and homozygous thalassemia are the 2 disorders for which there is an increasing demand for prenatal diagnosis in India. Rare severe deficiencies of coagulation factor X (FX) and factor VII (FVII) may present with severe bleeding manifestations. Because of their rarity the laboratory offering prenatal diagnosis for severe hemophilia and thalassemia may not be in a position to provide genetic diagnosis in the fetus. In this communication, we describe 2 families, 1 with an index patient of severe FVII deficiency and the other with severe FX deficiency where successful prenatal diagnosis was given after cordocentesis between 17 and 19 weeks using a battery of coagulation factor assays. Follow-up studies were performed 3 to 4 months after delivery and the diagnoses were reconfirmed on these babies by a repeat factor assay for FX and FVII deficiency, respectively.