RESUMO
BACKGROUND: Inherited thrombophilia (IT) has a complex pathophysiology and is associated with recurrent miscarriage (RM) by causing placental insufficiency and inhibiting fetal development. However, thrombophilia screening in unexplained RM cases is still questionable. This study aimed to investigate the association between the common eight IT mutations and their combinations among Palestinian women with unexplained RM. METHODS: This is an unmatched case-control study with 200 women (100 unexplained RM cases, 100 controls). Eight common IT mutations namely Factor V Leiden (FVL), prothrombin gene (FII) G202120A, Methylenetetrahydrofolate Reductase (MTHFR) gene (C677T and A1298C), B-fibrinogen gene - 455G > A, FV HR2 A4070G, Plasminogen activator inhibitor 1 (PAI1) 5G/4G and Factor XIIIA (FXIIIA) V34L; were analyzed. The first five mutations were analyzed by Restriction Fragment Length Polymorphism PCR and the other three mutations were analyzed using Amplification Refractory Mutation System PCR. RESULTS: The prevalence of the eight IT mutations among the control group was in the order PAI1 5G/4G (69%), MTHFR C677T (53%) and A1298C (47%), BFG - 455G > A (35%), FVL and FV HR2 (each 18%), FXIIIA V34L (16%) and FII G20210A (3%). Patients had a higher percentage of MTHFR A1298C (heterozygotes and mutant homozygote) compared to controls (p = 0.016). Frequencies of mutant alleles MTHFR A1298C (p < 0.001) and FXIIIA V34L (p = 0.009) were higher among patients compared to controls. No significant differences were observed for all other mutations or mutant alleles. Most patients (75%) and controls (75%) have 2-4 mutant alleles out of 8 mutant alleles studied, while 1% of patients and 2% of controls have zero mutant alleles. None of the combinations of the most often studied mutations (FVL, FII G20210A, MTHFR C1677T, and MTHFR A1298C) showed a significant difference between patients and controls. CONCLUSIONS: There was a significant association between unexplained RM and the mutant alleles of MTHFR A1298C and FXIIIA V34L. No significant association was observed between unexplained RM and the combination of both mutant alleles for the mutations studied. This study is the first Palestinian report that evaluates eight inherited thrombophilia mutations and their alleles' combinations in unexplained RM cases.
RESUMO
BACKGROUND: Multiple etiologies contribute to recurrent pregnancy loss (RPL) including immunological, endocrine, anatomical, genetic and infection but more than 50% of cases remain unexplained. Evidences of thrombotic and inflammatory processes were observed at maternal-fetal interface and considered pathological findings in most RPL cases including unexplained cases. This study aimed to evaluate the association between RPL and several risk factors: platelet parameters, coagulation factors, antiphospholipid syndrome, and thyroid function. METHODS: This is an unmatched case-control study that included 100 RPL and 100 control women. Anthropometric and health data were collected and a gynecologist examined participants to assure fitting the inclusion criteria. Platelet parameters [including Mean Platelet Mass (MPM), Concentration (MPC) and Volume (MPV)] and ratios (MPV/Platelet, MPC/Platelet, MPM/Platelet, Platelet/Mononuclear cells), coagulation markers [Protein C (PC), Protein S (PS), Antithrombin III, D-dimer], antiphospholipid antibodies [Anti-phospholipid (APA), Anti-cardiolipin (ACA) and anti-B2-glycoprotein 1], Lupus anticoagulant, Antinuclear antibodies, and thyroid function (Thyroid stimulating hormone and anti-thyroid peroxidase) were measured. RESULTS: Mean ages of cases and controls at marriage were 22.5 years for both, and their current ages were 29.4 and 33.0, respectively. 92% of cases and 99% of controls aged blow 30 years at marriage. 75% of cases have 3-4 miscarriages and 9% have ≥ 7 miscarriages. Our results indicated significantly lower male/female age ratio (p = .019), PC (p = .036) and PS (p = .025) in cases compared to controls. Plasma D-dimer (p = .020) and antiphospholipid antibodies [ACA (IgM and IgG), APA (IgM)] were significantly higher in cases compared to controls. No significant differences were observed between cases and controls concerning APA (IgG), anti-B2-glycoprotein 1 (IgM and IgG), Lupus anticoagulant, Antinuclear antibodies, platelet parameters, thyroid markers, family history of miscarriage, consanguineous marriage, and other health data. CONCLUSIONS: This is the first study that investigated the association between platelet, coagulation, antiphospholipid, autoimmune and thyroid parameters, and RPL in Palestinian women. Significant associations between male/female age ratio, PC, PS, D-dimer, ACA (IgM, IgG), APA (IgM) and RPL were observed. These markers could be used in evaluating RPL. These findings confirm the heterogeneous nature of RPL and emphasize the need for further studies to find out risk factors for RPL.
