Summary
The prevalence of haemostasis abnormalities was evaluated in 500 consecutive women
with unexplained primary recurrent miscarriages. Two matched reference groups with
no antecedent of miscarriage were studied: 100 healthy mothers and 50 childless women.
In the prospective part of the study, we found 9.4% of the patients (95% C.I.: 6.8-12%)
with an isolated factor XII deficiency, 7.4% of the patients (5.0-9.8%) with primary
antiphopholipid antibodies, 47% of the patients (42.6-51.4%) with an insufficient
response to the venous occlusion test and an isolated hypofibri- nolysis was found
in 42.6% (38.2-47%) of the patients (reference groups: respectively 0/150, 3/150,
2/150, 2/150, pclO’3). Willebrand disease, fibrinogen deficiency, antithrombin, protein C or protein S
deficiencies were not more frequent in recurrent aborters than in members of the reference
groups. In the retrospective part of the study, cases of plasma resistance to activated
protein C were not abnormally frequent.
Patients had higher Willebrand factor antigen (vWF), tissue-type plasminogen activator
antigen (t-PA), plasminogen activator inhibitor activity (PAI) and D-dimers (D-Di)
than the reference women. Values of vWF, t-PA, PAI and D-Di were altogether correlated
but were not related to C-reactive protein concentrations. Among patients, those with
an antiphospholipid syndrome and those with an insufficient response to the venous
occlusion test had higher vWF, t-PA, PAI and D-Di values than the patients with none
of the haemostasis-related abnormalities.
Thus, factor XII deficiency and hypofibrinolysis (mainly high PAI) are the most frequent
haemostasis-related abnormalities found in unexplained primary recurrent aborters.
In patients with antiphospholipid antibodies or hypofibrinolysis, there is a non-inflammatory
ongoing chronic elevation of markers of endothelial stimulation associated with coagulation
activation. This should allow to define subgroups of patients for future therapeutic
trials.
