Congenital hypofibrinogenemia in five members of a family.

The bleeding tendency in five members of one family with fibrinogen levels ranging from 58 mg. % to 158 mg. % was mild and chiefly related to dental extractions. Abruptio placentae in one patient produced severe bleeding. Reports of menstrual bleeding patterns in patients with defects of hemostatic mechanisms suggest that normal platelets, vascular function and extrinsic and possibly intrinsic coagulation systems, except for fibrinogen, control menstrual blood loss. An autosomal dominant gene with variable penetrance may determine fibrinogen levels.