Congenital blood coagulation factor XIII deficiency and successful deliveries: a review of the literature.

Congenital deficiency of blood coagulation factor XIII is an uncommon, inherited disorder characterized by hemorrhagic diathesis, habitual abortions and defective wound healing. We analyzed 8 reported successful pregnancies in women with a congenital deficiency of A-subunit of factor XIII (XIIIA), in which the plasma level of maternal factor XIIIA and/or the precise replacement therapies are described. Because decidual bleeding usually begins from 5 to 6 weeks' gestation and, without replacement therapy, spontaneous abortion always occurs, we herein offer the following prenatal and peripartum management guidelines and observations: i) the level of plasma A-subunit of factor XIII antigen (XIIIA-Ag) or factor XIII activity (XIII-act) must be at least 2%-3%, and, if possible, higher than 10% to prevent decidual bleeding and miscarriage during the pregnancy; ii) factor XIIIA concentrate is better than fresh frozen plasma or cryoprecipitate for replacement therapy; iii) the administration of 250 international units (IU) every 7 days is sufficient to maintain the level of plasma XIIIA-Ag or XIII-act more than 10% in the early period of gestation (through 22 weeks' gestation); however, 500 IU every 7 days is indicated in the later period (from 23 weeks' gestation) to maintain that level; iv) during labor, the desired level of plasma XIIIA-Ag or XIII-act should be higher than 20%, and, if possible, higher than 30% in order to make ready for any risk of severe obstetrical hemorrhagic complications; thus a booster dose of 1000 IU is indicated before labor; v) no replacement therapy is necessary in the puerperium because it is usually uneventful without it.