Factor VII deficiency and pregnancy.

Hereditary factor VII deficiency is very rare in pregnancy (one in 500,000). However, obstetricians should consider this diagnosis whenever the prothrombin time is prolonged while the activated partial thromboplastin time is normal. The factor VII level increases in normal pregnancy, but the effect of pregnancy upon the factor VII level in deficient individuals is unknown. We report two cases of factor VII deficiency in pregnancy. In both, factor VII levels were 15% or less in the third trimester and were lower postpartum, suggesting that pregnancy does elevate factor VII in deficient individuals as well. Fresh frozen plasma is the treatment of choice. If the level is very low, fresh frozen plasma can be given prophylactically; otherwise, it should be given if blood loss becomes excessive.