Genetic hypofibrinolysis in complicated pregnancies

Area of Science:

• Genetics and Obstetrics
• Thrombophilia Research

Background:

• Severe obstetric complications, including preeclampsia, abruptio placentae, fetal growth restriction, and stillbirth, pose significant risks to maternal and fetal health.
• The role of genetic factors, particularly those affecting fibrinolysis and coagulation, is increasingly recognized in the pathophysiology of these adverse pregnancy outcomes.

Purpose of the Study:

• To investigate the association between the hypofibrinolytic 4G/4G mutation in the plasminogen activator inhibitor (PAI-1) gene and severe obstetric complications.
• To determine if this mutation is an independent risk factor or if it interacts with other thrombophilic mutations.

Main Methods:

• A case-control study comparing 94 women with obstetric complications to 95 matched controls with normal pregnancies.
• DNA analysis was performed to identify the 4G/4G mutation in the PAI-1 gene, alongside testing for factor V Leiden, MTHFR C677T, and prothrombin G20210A mutations.

Main Results:

• Women with obstetric complications exhibited a higher prevalence of the PAI-1 4G/4G mutation (32% vs. 19%, OR=2.0).
• The 4G/4G mutation was independently associated with obstetric complications (OR=1.56).
• A significant association was observed between PAI-1 4G/4G homozygosity and factor V Leiden heterozygosity (33% vs. 0%, P=.008). Overall, 76% of women with complications had thrombophilia or hypofibrinolysis compared to 37% of controls (P<.001).

Conclusions:

• The hypofibrinolytic 4G/4G mutation of the PAI-1 gene is more frequent in women experiencing severe obstetric complications.
• This mutation is often associated with the thrombophilic factor V Leiden mutation, suggesting a combined effect that predisposes women to thrombosis during pregnancy.
• These genetic factors may contribute to the development of severe preeclampsia, abruptio placentae, fetal growth restriction, and stillbirth.