Moreover, we did not examine the maternal plasma levels of coagulation factor VIII, which had been reported to be associated with an increased risk for recurrent early pregnancy loss [24], or for protein Z deficiency and positive antiprotein Z antibodies, which had been described to increase the severity of the prothrombotic phenotype of FVL [25]. This evidence concerns the gene F8 and hyperinsulinemic hypoglycemia, familial, 4.