Coagulation and fibrinolysis markers in seminal plasma of patients under evaluation for involuntary childlessness.

Semen specimens from four groups of patients were evaluated for coagulation and fibrinolysis factors: a group of patients with infertile semen and involuntary childlessness (n = 35), a group with fertile semen and involuntary childlessness (n = 39), a group with fertile semen and proven fertility before vasectomy (n = 34) and a group with infertile semen after vasectomy (n = 147). The third patient group with proven fertility before vasectomy was considered as a control group. Only small amounts of fibrinogen, factor VIII:c, plasminogen, antithrombin III, fibrin monomers and plasminogen activator inhibitor-1 were detected in seminal plasma. The thrombin-antithrombin III, D-dimer and tissue plasminogen activator regular concentrations were measured and the D-dimer/thrombin-antithrombin III ratios calculated. The reference ranges were assessed and the quantities were compared in the different patient groups. Significant differences were demonstrated between the prevasectomy group (= control group) and both the postvasectomy and the infertility groups with respect to D-dimer and D-dimer/thrombin-antithrombin III ratio. We conclude that both coagulation and fibrinolysis play a part in coagulum formation and liquefaction of seminal plasma. The balance between coagulation and fibrinolysis (expressed as D-dimer/thrombin-antithrombin III ratio) was significantly different between the control group and the three patient groups. The coagulation/fibrinolysis balance was impaired in the semen from post vasectomy patients and from those with involuntary childlessness and the D-dimer/thrombin-antithrombin III ratios in both these patient groups were very similar.