Molecular diagnostic tests for thrombophilia in patients referred to genetic counseling clinic because due to recurrent pregnancy failure. One center’s experience.

The loss of three or more subsequent pregnancies before the end of the 22nd week is observed in 0.4–1% of women. Despite great advances in medicine, the causes of pregnancy failure (miscarriages, missed abortions and stillbirths), and the birth of a child or children with congenital abnormalities, are still not determined precisely. The aim: The purpose of the research was to determine the association of polymorphisms and mutations of coagulation factors II and V genes, as well as methylenetethrahydrofolate reductase (MTHFR) gene polymorphism, with the course of pregnancy and the type of reproductive failure. Methods: The research was performed in a group of 116 women referred to the Genetic Outpatient Clinic of the NCU SM in Bydgoszcz between 2009–2010 due to reproductive failures. The molecular tests for thrombophilia, i.e. mutation of the factor V Leiden, prothrombin gene mutation 20210G>A, and MTHFR polymorphism 677C>T were done in all patients. Results: The Leiden mutation was found in 8 women (homozygotic in 2 of them) and prothrombin gene mutation in 3. 85 women had the heterozygotic MTHFR polymorphism, while 24 the homozygotic one. Coexistence of the Leiden mutation and the MTHFR polymorphism was found in 3 patients with history of miscarriages. Conclusions: 1. The presence of the mutations that promote thrombophilia in the genes responsible for the foliate metabolism and for the plasma coagulation is often associated with pregnancy failures and may be their basic cause in some cases. 2. The percentage of women with pregnancy failures being heterozygotes (73.3%), homozygotes (20.7%) or both (94%) of the MTHFR gene 677C>T polymorphism is statistically significantly higher than the highest prevalence of these changes in the general population (55, 13%, and 68%, respectively). 3. The factor V gene Leiden mutation is associated mainly with recurrent spontaneous abortions. In the present study it was found only in the group of women with both early and late miscarriages