The factor V Leiden mutation is not a common cause of recurrent miscarriage

Pregnancy Loss, Polycystic Ovary Syndrome, Thrombophilia, Hypofibrinolysis, Enoxaparin, Metformin

Thrombophilia, hypofibrinolysis, and polycystic ovary syndrome (PCOS) are associated with recurrent pregnancy loss (RPL) and spontaneous abortion (SAB) alone and concurrently. The efficacy and safety of combined enoxaparin-metformin was prospectively assessed in women with PCOS with one or more previous SAB, thrombophilia, and/or hypofibrinolysis. Twenty-four white women with PCOS were studied; 23 with previous pregnancies, seven with RPL of unknown etiology (≥ three consecutive pregnancy losses <20 weeks’ gestation), two with two consecutive SABs, 13 with one SAB, and one with one live birth (HELLP syndrome). Prospectively, metformin (1.5 to 2.55 g/day) was administered before and throughout gestation, with concurrent enoxaparin (60 mg/day) throughout gestation. The 24 cases differed from 93 normal white female controls for the factor V Leiden mutation, 17% vs. 2%, Fisher’s p [pf] = .016, and for the 4G4G mutation of the plasminogen activator inhibitor-1 (PAI-1) gene (46% vs. 24%, Chi-square 4.63, p =. 031). The patients also differed from 44 normal white female controls for high levels (> 21.1 U/mL) of the PAI-1 gene product, plasminogen activator inhibitor activity (PAI-Fx) (33% vs. 8%, pf =. 018), and for high factor VIII (>150%) (22% vs. 0%, pf = .037). Of the 24 women, 23 had 65 previous pregnancies without metformin or enoxaparin, with 18 live births, 46 SAB (71%), and one elective abortion. On metforminenoxaparin, the same 23 women had 26 current pregnancies (28 fetuses), with 20 live births, two normal pregnancies 13 weeks or longer, and six SAB (21%), 3.4-fold lower than previous gestations (McNemar’s S = 33.6, p <. 0001). There were no adverse maternal or fetal therapy effects. Enoxaparin-metformin reduces pregnancy loss in women with PCOS with one or more previous SAB, who also have thrombophilia and/or hypofibrinolysis.

Infertility and miscarriage: common pathways in manifestation and management

The relationship between miscarriage and fertility is complex. While most healthcare settings treat miscarriage as a problem of subfertility in assisted reproduction units, others believe that miscarriage occurs in super-fertile women. Infertile women undergoing assisted reproduction are at a greater risk of having a miscarriage especially at an advanced age compared with women conceiving naturally. Aberrant expression of immunological factors and chromosomal abnormalities underlie both infertility and miscarriage. Common risk factors include increased maternal age, obesity, smoking, alcohol, pre-existing medical conditions and anatomical abnormalities of the reproductive system. Management pathways of both conditions may be similar with pre-implantation genetic testing and assisted reproductive technology used in both conditions. This paper discusses the synergies and differences between the two conditions in terms of their epidemiology, etiopathogenesis, risk factors and management strategies. The two conditions are related as degrees of severity of reproductive failure with common pathways in manifestation and management.

Lack of Association between Recurrent Pregnancy Loss and Inherited Thrombophilia in a Group of Colombian Patients

Studies have shown an association between recurrent pregnancy loss and inherited thrombophilia in Caucasian populations, but there is insufficient knowledge concerning triethnic populations such as the Colombian. The aim of this study was to evaluate whether inherited thrombophilia is associated with recurrent pregnancy loss. Methods. We conducted a case-control study of 93 patients with recurrent pregnancy loss (cases) and 206 healthy multiparous women (controls) in a Colombian subpopulation. Three single nucleotide polymorphisms (SNPs) markers of the inherited thrombophilias factor V Leiden, prothrombin G20210A, and methylenetetrahydrofolate reductase C677T were genotyped by PCR-RFLP. Activated protein C resistance and plasma levels of antithrombin, protein C, and protein S were also measured. Results. The frequency of thrombophilia-associated SNPs, activated protein C resistance, and anticoagulant protein deficiencies, was low overall, except for the methylenetetrahydrofolate reductase C677T SNP. The differences between patients and controls had no statistical significance. Conclusion. Our study confirms the low prevalence of inherited thrombophilias in non-Caucasian populations and it is unlikely that the tested thrombophilias play a role in the pathogenesis of recurrent pregnancy loss in this Colombian population.

Impact of smoking during pregnancy on functional coagulation testing

Compounds that are systemically absorbed during the course of cigarette smoking, and their metabolites, affect the coagulation system and cause endothelial dysfunction, dyslipidemia, and platelet activation leading to a prothrombotic state. In addition, smoking increases the activity of fibrinogen, homocysteine, and C-reactive protein. We hypothesize that smoking may affect functional coagulation testing during pregnancy. A secondary analysis of 371 women pregnant with a singleton pregnancy and enrolled in a multicenter, prospective observational study of complications of factor V Leiden mutation subsequently underwent functional coagulation testing for antithrombin III, protein C antigen and activity, and protein S antigen and activity. Smoking was assessed by self-report at time of enrollment (<14 weeks). None of the functional coagulation testing results was altered by maternal smoking during pregnancy. Smoking does not affect the aforementioned functional coagulation testing results during pregnancy.

Association of elevated soluble P-selectin levels with fetal loss in women with a history of venous thromboembolism

INTRODUCTION

An association between pregnancy complications such as fetal loss with inherited and acquired thrombophilic defects has frequently been reported. Recently, the cell adhesion molecule P-selectin has been identified to be a strong risk factor for venous thromboembolism (VTE).

PATIENTS AND METHODS

The aim of our study was to investigate whether soluble P-selectin (sP-selectin) is also associated with fetal loss (e.g. miscarriage or stillbirth) in 304 women (median age [25th-75th percentile]: 45 [37-54] years) with a history of VTE, in whom data on pregnancy-associated complications had been evaluated. At the time of sP-selectin measurement none of the women was pregnant or had an acute VTE.

RESULTS

The prevalence of miscarriage was 21.4% and that of stillbirth was 4.6%. The median sP-selectin level of the total study population was 38.0 [31.7-44.4] ng/mL. In subjects with elevated sP-selectin levels (defined as sP-selectin ≥44.4ng/mL, representing the 75th percentile of levels in the study population) the prevalence of stillbirth was significantly higher compared to those with lower levels (10.5% vs. 2.6%, p=0.008), whereas no statistically significant difference in the prevalence of miscarriage was observed between women with and without elevated sP-selectin (17.1% vs. 22.9%, p=0.303). The odds ratio [95% CI] of elevated sP-selectin was 4.2 [1.5-12.7] for stillbirth and 0.7 [0.4-1.3] for miscarriage.

CONCLUSIONS

Elevated sP-selectin plasma levels were associated with a 4.2-fold risk for stillbirth in women with a history of VTE. Our data support a possible role of P-selectin in late pregnancy loss.

Hereditary thrombophilia, anti-beta2 glycoprotein 1 IgM, and anti-annexin V antibodies in recurrent pregnancy loss

PROBLEM

We investigated the beta2-glycoprotein I and anti-annexin V antibodies as anti-phospholipid-cofactor antibodies; and factor V G1691A Leiden, prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T mutations as hereditary thrombophilia in recurrent pregnancy losses (RPL).

METHOD OF STUDY

Study group consisted of 84 women with recurrent pregnancy loss and control group consisted of 84 women having at least one live birth.

RESULTS

Methylenetetrahydrofolate reductase C677T homozygous mutation was detected in 28.5% of the study group and in 14.2% of the controls, and the difference was highly significant (P < 0.001). Heterozygous mutation of this gene was found in 64.3% of the study population and in 38.1% of the controls, and difference in heterozygous mutation frequency was also significant (P < 0.001). Both homozygous and heterozygous mutations of PT G20210A and factor V G1691A were not different between the groups. There was no significant difference in anti-annexin V levels and anti-beta2-gp 1 levels of the groups.

CONCLUSION

We concluded that both homozygous and heterozygous mutations of MTHFR C677T were related with RPL in Caucasian women.

Can Factor V Leiden and prothrombin G20210A testing in women with recurrent pregnancy loss result in improved pregnancy outcomes?: Results from a targeted evidence-based review

Women with recurrent pregnancy loss are offered Factor V Leiden (F5) and/or prothrombin G20210A (F2) testing to identify candidates for anticoagulation to improve outcomes. A systematic literature review was performed to estimate test performance, effect sizes, and treatment effectiveness. Electronic searches were performed through April 2011, with review of references from included articles. English-language studies addressed analytic validity, clinical validity, and/or clinical utility and satisfied predefined inclusion criteria. Adequate evidence showed high analytic sensitivity and specificity for F5 and F2 testing. Evidence for clinical validity was adequate. The summary odds ratio for association of recurrent pregnancy loss with F5 in case-controlled studies was 2.02 (95% confidence interval, 1.60-2.55), with moderate heterogeneity and suggestion of publication bias. Longitudinal studies in women with recurrent pregnancy loss or unselected cohorts showed F5 carriers were more likely to have a subsequent loss than noncarriers (odds ratios: 1.93 and 2.03, respectively). Results for F2 testing were similar. For clinical utility, evidence was adequate that anticoagulation treatments were ineffective (except in antiphospholipid antibody syndrome) and had treatment-associated harms. The certainty of evidence is moderate (high, moderate, and low) that anticoagulation of women with recurrent pregnancy loss and F5/F2 variants would currently lead to net harms.

Comparative evaluation of Tissue factor and Thrombomodulin activity changes during normal and idiopathic early and late foetal loss: the cause of hypercoagulability?

Various components of the coagulation and fibrinolytic pathways are involved in normal embryonic implantation, trophoblast invasion, placentation, and recurrent miscarriages are characterized by defective placentation and microthrombi in the placental vasculature. Although recurrent miscarriage is a heterogeneous condition the relationship between abnormalities in the haemostatic pathways and pregnancy outcome is increasingly recognized. The challenge we face is how to discriminate between women who are destined to miscarry from those whose pregnancy will be successful. Considering the crucial role of thrombomodulin and tissue factor in coagulation and in embryonic development, we have performed a study using specific assays for thrombomodulin, tissue factor activity and procoagulant phospholipids in association with other parameters in 30 early (under 12weeks) and 32 late (over 22weeks) pregnancy loss women and compared them with 62 normal pregnancy women and 35 non-pregnant women. Plasma levels of tissue factor activity, thrombomodulin activity, and procoagulant phospholipids were significantly higher in patients than in control subjects. In addition the tissue factor activity/free tissue factor pathway inhibitor ratio was higher in patients than in controls. Interestingly, patients with late pregnancy loss had higher tissue factor activity/free tissue factor pathway inhibitor ratios than patients with early pregnancy loss. The combinations of these different parameters reveal an increase in procoagulant activity which could be secondary to endothelial damage or coagulation activation and then are involved in the pathogenesis of pregnancy loss. Their simultaneous measurement of these activities might provide a new tool to assess the prognosis of pregnancy loss.

A prospective case-control study analyzes 12 thrombophilic gene mutations in Turkish couples with recurrent pregnancy loss

PROBLEM

Recurrent pregnancy loss (RPL) is a heterogeneous disorder. The contribution of specific thrombophilic genes to the pathophysiology of RPL has remained controversial. We evaluated the prevalences of 12 thrombophilic gene mutations among homogenous Caucasian couples with RPL and fertiles.

METHOD

of study This was a prospective case-control study evaluating 272 women with RPL and 152 of their male partners, and a control group of 56 fertile couples. We investigated mutations including FV Leiden, factor V H1299R, factor II prothrombin G20210A, F XIII V34L, beta-fibrinogen -455G>A, plasminogen activator inhibitor-1, GPIIIa L33P (HPA-1 a/b L33P), MTHFR C677T, MTHFR A1298C, ACE I/D, Apo B R3500Q, and Apo E.

RESULTS

Overall, heterozygous mutations of FV Leiden, FXIII V34L, GPIIIa L33P, Apo E4, and prothrombin G20210A and homozygous mutations of PAI-1and MTHFR C677T were associated with RPL. There was no meaningful association between RPL and other studied genes.

CONCLUSION

In contrast to the other mutations and polymorphisms, FV Leiden, FXIII V34L, GPIIIa L33P, Apo E, prothrombin G20210A, PAI-1 and MTHFR C677T gene mutations may help to identify the couples at risk for recurrent pregnancy loss.

Paternal thrombophilic gene mutations are not associated with recurrent miscarriage

PROBLEM

Recurrent miscarriage (RM) affects 1-3% of couples. So far, diagnostic procedures are performed only in female patients. However, the main part of the placentary perfusion is encoded by both the maternal and the paternal genome.

METHOD OF STUDY

In this case-control study, German couples with two (n = 49) or three and more RM (n = 102) and 157 German control couples were analyzed for the factor V-Leiden 169 1G > A mutation (FVL), the prothrombin (PT) 202 10G > A substitution, and the 677C > T replacement in the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene.

RESULTS

No significant differences in the prevalence of the FVL, PT or MTHFR mutation were observed in male partners of RM patients and in control men [RM/control: FVL heterozygous 13/151 (8.6%): 14/157 (8.9%) (P = 0.9); PT heterozygous 2/151 (1.3%): 7/157 (4.5%) (P = 0.097); PT homozygous 0/151: 2/157 (1.3%); MTHFR homozygous 19/151 (12.6%): 18/157 (11.5%) (P = 0.12)]. This was also true for female RM patients. However, miscarriage during the embryonal period (5-10 weeks of gestation) was significantly associated with a maternal heterozygous FVL mutation (P = 0.014).

CONCLUSION

Recurrent miscarriage was not associated with paternal thrombophilia. Men of the control group showed an even higher incidence of the PT and MTHFR mutations. Abortions in the embryonic phase of fetal development were associated with a significantly higher incidence of maternal heterozygosity for FVL.

Inherited thrombophilias and unexplained pregnancy loss: an incident case-control study

BACKGROUND

Despite an initial impressive impact, a critical appraisal of the link between pregnancy loss and inherited thrombophilias is currently growing. Furthermore, little is known about the paternal thrombophilic phenotype and pregnancy loss.

OBJECTIVE

We sought an association between unexplained pregnancy loss and parental factor V Leiden (FVL) and Prothrombin G20210A (PTG) mutations.

METHODS

Design - Incident case-control study. Setting- University Hospital of Brest (France). Patients - Women and their partners from the West Brittany area, consecutively referred for unexplained pregnancy losses (two or more consecutive losses at or before 21 weeks of gestation, or at least one later loss). Controls - Women and their partners with no history of pregnancy loss and at least one normal pregnancy, from the same geographic area, recruited using electoral lists. Statistical analysis - Comparison of FVL and PTG allele frequency between cases and controls using the chi-square test. Separate analyses were performed according to the type of pregnancy loss (early recurrent or later loss).

RESULTS

311 women (mean age: 32.8) and 284 of their partners were enrolled as cases while 599 women (mean age: 34.3) and 297 of their partners were recruited as controls. The prevalence of female, male or couple thrombophilic mutations was not statistically different between cases and controls whatever the definition of pregnancy loss retained.

CONCLUSIONS

Presently, there is no clinical indication to routinely test for FVL and likely PTG mutations in women with early recurrent pregnancy loss. Moreover, our results did not reveal that paternal thrombophilic polymorphism should be further explored.

Factor V Leiden and G20210A prothrombin mutations in patients with recurrent pregnancy loss: data from the southeast of Turkey

Factor V Leiden (FV-Leiden) and prothrombin gene mutations (FII G20210A) are well-established independent risk factors for thrombosis. In the recent years, many studies have suggested that these mutations are associated with an increased risk of recurrent pregnancy loss (RPL). We aimed to investigate the prevalence of these molecular defects in subjects with a history of early RPL. One hundred and fourteen women with three or more consecutive unexplained first-trimester miscarriages were compared to 185 parous women with uncomplicated pregnancies from the same ethnic origin. The presence of FV-Leiden and FII G20210A mutations was assessed by polymerase chain reaction analysis. Overall, 11 out of the 114 women with early RPL (9.6%) had either FV-Leiden or FII G20210A mutation, as compared with 16 out of the 185 women with normal pregnancies (8.6%; p = 0.756). The prevalence of FV-Leiden mutation was 7.9% (9/114) in patient group, compared with 7% (13/185) in control group (p = 0.780). One hundred and two patients were primary and 12 were secondary aborters. All FV-Leiden positive cases were primary aborters (8.8%; 9/102, p = 0.584). Concerning the FII G20210A, two out of 114 (1.7%) were first-trimester RPL (primary aborters) and three out of 185 (1.6%) controls were carriers of the FII G20210A mutation (1.7 vs 1.6%, p = 0.931). The results obtained from patients with first-trimester RPL and the control group have no statistical significant differences in the prevalence of FV-Leiden and FII G20210A mutations. These results suggest that mutations have no role in etiology of first-trimester recurrent abortions.

Causes of Fetal Wastage

Fetal wastage has many causes, but genetic factors are by far the most common. The earlier the pregnancy loss occurs, the greater the likelihood of genetic causation. Among first trimester abortions, 50% to 80% show chromosomal abnormalities, usually aneuploidy. This is greater than all other causes combined. Chromosomal numerical abnormalities can be recurrent and sporadic; failure to take this into account is a major pitfall in many reports addressing causation. Moreover, many causes of fetal wastage that are traditionally considered to be "nongenetic" are actually the result of perturbations of gene products-proteins. Among nongenetic causes of first trimester fetal wastage, the best established are thyroid abnormities; antifetal antibodies; and the inherited and acquired thrombophilias. The latter are more established in the second trimester. Uterine anomalies can lead to second trimester losses. Infections seem uncommon, and alloimmune causes are not validated.

Multiple thrombophilic gene mutations rather than specific gene mutations are risk factors for recurrent miscarriage

PROBLEM

Recurrent miscarriage is a heterogeneous condition. While the role of acquired thrombophilia has been accepted as an etiology of recurrent miscarriage, the contribution of specific inherited thrombophilic genes to this disorder has remained controversial. We compared the prevalence of 10 thrombophilic gene mutations among women with a history of recurrent miscarriages and fertile control women.

METHOD OF STUDY

A total of 150 women with a history of two or more recurrent pregnancy losses and 20 fertile control women with no history of pregnancy losses had buccal swabs taken for DNA analyses of 10 gene mutations [factor V G1691A, factor V H1299R (R2), factor V Y1702C, factor II prothrombin G20210A, factor XIII V34L, beta-fibrinogen -455G>A, PAI-1 4G/5G, HPA1 a/b (L33P), MTHFR C677T, MTHFR A1298C]. The prevalence of these mutations was compared between women experiencing recurrent miscarriage and controls.

RESULTS

No differences in the frequency of specific gene mutations were detected when women with recurrent miscarriage were compared with control women. However, the prevalence of homozygous mutations and total gene mutations among patients with recurrent miscarriage was significantly higher than among controls. Homozygous mutations were found in 59% of women with a history of recurrent pregnancy loss contrasted to 10% of control women. More than three gene mutations among the 10 genes studied were observed in 68% of women with recurrent miscarriage and 21% of controls.

CONCLUSION

Inherited thrombophilias are associated with recurrent miscarriage. This association is manifest by total number of mutations rather than specific genes involved.

Trombofilia congénita y aborto recurrente: estrategias diagnósticas y recomendaciones terapéuticas

Pregnancy is a well recognized thrombophilic risk factor. Recurrent abortion (RA) affect up to 3% of fertile couples. A 50% of these cases are considered as idiopathic. Some of them may have one or more than one thrombophilic alterations. RA may be related to placental flow abnormalities. Up to 1% to 5% of all pregnancies may be complicated with placental flow abnormalities. Antiphospholipid syndrome, PS, PC, ATIII deficiencies, factor V, prothrombin, methylentetrahydrofolate reductase, plasminogen activator inhibitor type 1, fibrinogen and factor XIII polymorphisms, have been strongly related to bad obstetric outcomes, specially RA. The presence of more than one thrombophilic factor may be present in pregnant women, rising the risk of suffering RA. All pregnant patients and those who planed a future conception having a history of thrombotic events, independently of their previous obstetric outcomes, need to be studied for thrombophilia. All patients with RA specially if it appeared in the late-pregnancy, have also to be studied. Early antiaggregant and/or anticoagulant therapy, reduces the maternal-fetal risk.

Association between adverse pregnancy outcomes and maternal factor V G1691A (Leiden) and prothrombin G20210A genotypes in women with a history of recurrent idiopathic miscarriages

Thrombophilia was implicated in the development of pregnancy complications, including recurrent idiopathic pregnancy loss, and is aggravated in women who are carriers of factor V G1691A (FV Leiden) and prothrombin (PRT) G20210A single-nucleotide polymorphisms (SNPs). Previous studies examined the role of FV-Leiden and PRT G20210A in recurrent pregnancy loss with conflicting results. Here we examined the prevalence of FV Leiden and PRT G20210A SNPs, in 200 women with 3 or more consecutive early (n = 87), late (n = 41), or early-late (n = 72) recurrent pregnancy losses, and 200 age-matched fertile parous control women. APC resistance (APCR) was detected functionally (measuring the activated clotting time triggered by activated factor X in presence of a fixed amount of purified APC), and FV-Leiden and PRT G20210A genotypes were assessed by PCR. The frequency of the mutant FV (0.1400 vs. 0.0276; P < 0.001) but not PRT 20210 (0.0100 vs. 0.0225; P = 0.159) allele was higher in patients than controls, respectively. APC resistance with factor V Leiden was seen in 27% of patients compared to 11.5% of controls, while APC resistance without factor V Leiden was seen in 12.5% of patients compared to 9.5% of controls. Regression analysis demonstrated that the significant predictors for early abortion was FV Leiden; those for late abortion were oral contraceptive, APCR, and FV Leiden; and predictors for early-late abortions were oral contraceptives, obesity, FV Leiden, and smoking. APC resistance and FV Leiden, as well as combination of both, are common thrombotic defects seen in women with idiopathic recurrent pregnancy loss, thus testing for these is recommended in women who have experienced recurrent miscarriages.

The Relationship of the Factor V Leiden Mutation and Pregnancy Outcomes for Mother and Fetus

OBJECTIVE

We sought to estimate the frequency of pregnancy-related thromboembolic events among carriers of the factor V Leiden (FVL) mutation without a personal history of thromboembolism, and to evaluate the impact of maternal and fetal FVL mutation carriage or other thrombophilias on the risk of adverse outcomes.

METHODS

Women with a singleton pregnancy and no history of thromboembolism were recruited at 13 clinical centers before 14 weeks of gestation from April 2000 to August 2001. Each was tested for the FVL mutation, as was the resultant conceptus after delivery or after miscarriage, when available. The incidence of thromboembolism (primary outcome), and of other adverse outcomes, was compared between FVL mutation carriers and noncarriers. We also compared adverse outcomes in a secondary nested carrier-control analysis of FVL mutation and other coagulation abnormalities. In this secondary analysis, we defined carriers as women having one or more of the following traits: carrier for FVL mutation, protein C deficiency, protein S deficiency, antithrombin III deficiency, activated protein C resistance, or lupus anticoagulant-positive, heterozygous for prothrombin G20210A or homozygous for the 5,10 methylenetetrahydrofolate reductase mutations. Carriers of the FVL mutation alone (with or without activated protein C resistance) were compared with those having one or more other coagulation abnormalities and with controls with no coagulation abnormality.

RESULTS

One hundred thirty-four FVL mutation carriers were identified among 4,885 gravidas (2.7%), with both FVL mutation status and pregnancy outcomes available. No thromboembolic events occurred among the FVL mutation carriers (0%, 95% confidence interval 0-2.7%). Three pulmonary emboli and one deep venous thrombosis occurred (0.08%, 95% confidence interval 0.02-0.21%), all occurring in FVL mutation noncarriers. In the nested carrier-control analysis (n = 339), no differences in adverse pregnancy outcomes were observed between FVL mutation carriers, carriers of other coagulation disorders, and controls. Maternal FVL mutation carriage was not associated with increased pregnancy loss, preeclampsia, placental abruption, or small for gestational age births. However, fetal FVL mutation carriage was associated with more frequent preeclampsia among African-American (15.0%) and Hispanic (12.5%) women than white women (2.6%, P = .04), adjusted odds ratio 2.4 (95% confidence interval 1.0-5.2, P = .05).

CONCLUSION

Among women with no history of thromboembolism, maternal heterozygous carriage of the FVL mutation is associated with a low risk of venous thromboembolism in pregnancy. Neither universal screening for the FVL mutation, nor treatment of low-risk carriers during pregnancy is indicated.

LEVEL OF EVIDENCE

II-2.

Prevalence of antiphospholipid antibodies, factor V G1691A (Leiden) and prothrombin G20210A mutations in early and late recurrent pregnancy loss

OBJECTIVE

We assessed the prevalence of inherited (FV-Leiden and PRT G20210A), and acquired (anti-PL antibodies) risk factors among habitual aborters in Tunisia.

STUDY DESIGN

We studied prospectively 146 patients with > or =3 consecutive early, late, or early-late recurrent pregnancy losses, together with 99 age-matched controls. Anticardiolipin antibodies (ACL), lupus anticoagulant (LA), and APC resistance (APCR) were detected by ELISA, dilute Russell Viper Venom Time (dRVVT), and coagulation tests, respectively, and FV-Leiden and PRT G20210A genotypes were assessed by PCR.

RESULTS

Anti-PL antibody frequencies were 45 and 9% among patients and controls, respectively (P < 0.001), with positive LA only (P = 0.004), or combined elevated ACL-positive LA being consistently higher (P < 0.001) among patients than controls. FV-Leiden (20.54% versus 6.06%), but not PRT G20210A (2.74% versus 4.04%) was significantly higher in patients versus controls. Among LA-positive cases higher prevalence of G/A (14/146 versus 1/99) and A/A genotypes (4/146 versus 0/99) were seen, and among ACL-positive cases higher prevalence of G/A (10/146 versus 0/99) and A/A genotypes (2/146 versus 0/99) were recorded.

CONCLUSIONS

Anti-PL antibodies and FV-Leiden, but not PRT G20210A, are associated with recurrent idiopathic pregnancy losses in Tunisian women.

Evidence-based care of recurrent miscarriage

Between 0.5 and 1.0% of couples experience recurrent pregnancy loss (RPL), which is defined as three or more consecutive miscarriages. Losses are classified as pre-embryonic (<5 weeks), embryonic (5-10 weeks) or fetal (>10 weeks). Genetic abnormalities are responsible for RPL in 2-4% of these couples. Inadequate progesterone production has been proposed a cause of RPL and progesterone is given to prevent miscarriage, despite a lack of supportive evidence. The factor V Leiden and prothrombin G20210A mutations are common inherited thrombophilias also associated with RPL. Antenatal thromboprophylaxis is sometimes recommended although no data exist regarding efficacy. Antiphospholipid syndrome is known to cause RPL and antenatal thromboprophylaxis reduces the risk of miscarriage. Uterine abnormalities might also result in RPL. About 50% of cases of RPL have no identifiable cause. Alloimmune incompatibility has been proposed as a cause for RPL in these women. The concept of alloimmune-related RPL has not been scientifically validated.

Thrombophilias and recurrent pregnancy loss: a critical appraisal of the literature

Thrombophilias are suggested to play a role in recurrent miscarriage. The aim of this study was to evaluate the literature of the past 10 years regarding the association between thrombophilias and recurrent miscarriage. We concluded that there is a large variety in applied study methodology. Therefore, we defined criteria for an adequate study on the relationship of thrombophilias on recurrent pregnancy loss: (i) no exclusion criteria for patients or at least the same criteria for patients and controls; (ii) a clear definition of the gestational age at previous losses; (iii) a well-described control group; (iv) clear description of the test methods and moment of testing; and (v) a clear description of the (non) significant differences or odds ratio between cases and controls. Eleven out of 69 studies fulfilled these criteria. Their results show significant higher serum homocysteine levels among women with a history of recurrent miscarriage. No relation was found between recurrent miscarriage and the methylenetetrahydrofolate reductase C667T mutation. No relation was observed for the levels of antithrombin, protein C and protein S. Seven studies on the association of factor V Leiden (FVL) and/or pathologic activated protein C ratio (pAPCR) showed that FVL may play a role in second trimester losses, as do antiphospholipid antibodies. Studies on the prothrombin gene mutation yielded conflicting results. Consequently, large prospective studies according to the aforementioned criteria are needed to establish if there is a relationship between thrombophilias and recurrent miscarriage at all. At present, there is only justification for testing for homocysteine levels, antiphospholipid antibodies and FVL in women with a history of recurrent miscarriage.

Association of anticardiolipin antibody and C677T in methylenetetrahydrofolate reductase mutation in women with recurrent spontaneous abortions: a new path to thrombophilia?

CONTEXT

Recurrent spontaneous abortion (RSA) has been associated with venous thrombosis in the mother. Acquired and inherited thrombophilia factors are possible causes.

OBJECTIVE

To evaluate the association between thrombogenic factors and recurrent spontaneous abortion.

TYPE OF STUDY

Case-control study.

SETTING

Centro de Atenção Integral à Saúde da Mulher, Universidade Estadual de Campinas.

METHODS

40 ml of blood was collected from 88 women attending an RSA clinic and 88 fertile women attending a family planning clinic, to evaluate the presence of acquired and inherited thrombophilia factors. Anticardiolipin antibodies (ACA), lupus anticoagulant and deficiencies of proteins C and S and antithrombin III were evaluated by enzyme-linked immunosorbent assay (ELISA), dilute Russell Viper Venom time (dRVVT), coagulometric and chromogenic methods. DNA was amplified by the polymerase chain reaction (PCR) to study factor V Leiden and G20210A mutations in the prothrombin gene and C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene. Data were analyzed using odds ratios and a regression model for age adjustment. Fishers exact test was used to evaluate statistical relationships between associated factors and RSA.

RESULTS

ACA was detected in 11 women with RSA and one fertile woman. Heterozygous C677T was detected in 59 women with RSA and 35 fertile women. Concomitant presence of ACA and C677T was found in eight women with RSA and no fertile women (p < 0.01).

DISCUSSION

The meaning of the association between C677T mutation in the MTHFR gene and ACA is still not clear. It is possible that an inherited factor that alone would not strongly predispose a woman to thrombosis could, when associated with an acquired factor, start the process and increase the likelihood of thrombosis expression.

CONCLUSIONS

ACA and C677T in the MTHFR gene are statistically associated with RSA. The association of these two conditions is a new finding in thrombogenic factors and RSA.

Thrombophilia and pregnancy complications

OBJECTIVE

This systematic review examines the strength of the association between thrombophilia and recurrent pregnancy loss and other serious obstetric complications. Study design Electronic databases and manual bibliography searches were used to identify studies evaluating the association between thrombophilia and pregnancy loss, preeclampsia, fetal growth retardation, and placental abruption.

RESULTS

Thrombophilic disorders are associated with an increased risk of fetal loss in the majority of case control and cohort studies. The risk is increased throughout pregnancy, but may be higher in the second and third trimester. The common pathologic finding of placental infarction suggests unexplained fetal loss may result from uteroplacental insufficiency and thrombosis. Thrombophilic disorders are not consistently associated with preeclampsia, fetal growth retardation, or placental abruption. Preliminary data suggest prophylactic anticoagulation may improve outcome in thrombophilic women with unexplained recurrent fetal loss.

CONCLUSION

Women with thrombophilia have an increased risk of pregnancy loss and possibly other serious obstetric complications, although definition of the magnitude of risk will require prospective longitudinal studies. Preliminary data suggesting prophylactic anticoagulation may improve gestational outcome provide a rationale for prospective randomized trials in thrombophilic women with unexplained recurrent fetal loss.

Placental pathology in fetal thrombophilia

The aim of this study was to test the hypothesis that placental vascular lesions of the fetal circulation are caused by fetal thrombophilic mutations. The study included 64 newborns of women with one or more of the following pregnancy complications: preeclampsia, placental abruption, and intrauterine growth restriction. The most prevalent inherited thrombophilias--factor V Leiden, factor II (prothrombin) G20210A, and homozygosity for methyltetrahydrofolate reductase C677T--were examined in maternal blood and fetal umbilical cord blood. One pathologist reviewed all of the slides for fetal vascular lesions. Associations between fetal thrombotic vasculopathy and fetal thrombophilia were tested for using Fisher's exact test; Z scores and gestational age were compared using the Student t-test. Fetal thrombophilic mutations were diagnosed in 19 of 64 newborns, 15 of whom had coexistent maternal thrombophilia. There was no statistical difference in the prevalence of thrombotic lesions of the fetal circulation between newborns with and without thrombophilia. The combination of maternal and fetal thrombophilia was also not associated with increased fetal vascular lesions. The results indicate that fetal thrombophilia alone, even in the context of maternal underperfusion, is not associated with fetal vascular lesions of the placenta, although it may represent an underlying risk factor for lesions triggered by other process(es).

Hereditary thrombophilia and fetal loss: a prospective follow-up study

BACKGROUND

As the placental vessels are dependent on the normal balance of procoagulant and anticoagulant mechanisms, inherited thrombophilia may be associated with fetal loss.

OBJECTIVES

We performed a prospective study to investigate the relation between inherited thrombophilia and fetal loss, and the influence of thromboprophylaxis on pregnancy outcome.

PATIENTS AND METHODS

Women were enrolled in the European Prospective Cohort on Thrombophilia (EPCOT). These included women with factor (F)V Leiden or a deficiency of antithrombin, protein C or protein S. Controls were partners or acquaintances of thrombophilic individuals. A total of 191 women (131 with thrombophilia, 60 controls) had a pregnancy outcome during prospective follow-up. Risk of fetal loss and effect of thromboprophylaxis were estimated by frequency calculation and Cox regression modelling.

RESULTS

The risk of fetal loss appeared slightly increased in women with thrombophilia without a previous history of fetal loss who did not use any anticoagulants during pregnancy (7/39 vs. 7/51; relative risk 1.4; 95% confidence interval 0.4, 4.7). Per type of defect the relative risk varied only minimally from 1.4 for FV Leiden to 1.6 for antithrombin deficiency compared with control women. Prophylactic anticoagulant treatment during pregnancy in 83 women with thrombophilia differed greatly in type, dose and duration, precluding solid conclusions on the effect of thromboprophylaxis on fetal loss. No clear benefit of anticoagulant prophylaxis was apparent.

CONCLUSIONS

Women with thrombophilia appear to have an increased risk of fetal loss, although the likelihood of a positive outcome is high in both women with thrombophilia and in controls.

Polycystic ovary syndrome, the G1691A factor V Leiden mutation, and plasminogen activator inhibitor activity: associations with recurrent pregnancy loss

Our specific aim was to assess associations of thrombophilia, hypofibrinolysis, and polycystic ovary syndrome (PCOS) with recurrent pregnancy loss (RPL) (>/=3 consecutive pregnancy losses < 20 weeks gestation). Prospective studies were performed in 33 Caucasian women referred for diagnosis and treatment of PCOS who were subsequently found to have RPL and in 16 Caucasian women referred for diagnosis and treatment of RPL, who did not have PCOS. Cases (PCOS-RPL, RPL without PCOS) were compared with controls (116 healthy Caucasian females) for the G1691A Factor V Leiden, G20210A prothrombin, C677T methylenetetrahydrofolate reductase (MTHFR), plasminogen activator inhibitor 4G/5G, and platelet glycoprotein PL A1A2 gene mutations. Cases were compared with controls (44 healthy adult Caucasian females) for serologic coagulation tests including homocysteine, proteins C, S, free S, antithrombin III, anticardiolipin antibodies IgG and IgM, dilute Russel's viper venom time, activated partial thromboplastin time, Factor VIII, Factor XI, lipoprotein (Lp)(a), and plasminogen activator inhibitor activity (PAI-Fx). The 33 Caucasian women with PCOS subsequently found to have RPL were 10% of a cohort of 322 Caucasian women who had >/= 1 previous pregnancy and had been referred for diagnosis and therapy of PCOS over a 4.3-year period. The Factor V Leiden G1691 mutation was present in 6 of 33 women (18%) with PCOS-RPL and in 3 of 16 women with RPL without PCOS (19%) versus 2 of 116 (1.7%) female controls, Fisher's P (p(f)) =.0016, p(f) =.013. The 33 PCOS-RPL cases also differed from the 44 female controls for high PAI-Fx (>21.1 U/mL), 38% versus 8%, p(f) =. 004. The thrombophilic G1691A Factor V Leiden mutation is associated with RPL in women with and without PCOS; hypofibrinolysis (high PAI-Fx) is also associated with RPL in women with PCOS.

Thrombophilia and pregnancy

Pregnancy is hypercoagulable state. The field of thrombophilia; the tendency to thrombosis, has been developed rapidly and has been linked to many aspects of pregnancy. It is recently that severe pregnancy complications such as severe preeclampsia intrauterine growth retardation abruptio placentae and stillbirth has been shown to be associated with thrombophilia. Recurrent miscarriage and has also been associated with thrombophilia. Finally, thromboembolism in pregnancy as in the non-pregnant state is linked to thrombophilia. In this review all aspects of thrombophilia in pregnancy are discussed, and also all prophylactic and therapeutic implications.

Analyzes of three common thrombophilic gene mutations in German women with recurrent abortions

BACKGROUND

Several etiological factors have been proposed as a cause for recurrent fetal abortions. Changes in blood coagulation during pregnancy may play an important role in the occurrence of recurrent abortions (RA).

METHODS

The aim of this study was to investigate the prevalence of factor V Leiden, factor II prothrombin, and methylenetetrahydrofolate reductase (MTHFR) mutations in women with recurrent abortions (> or =2 abortions) in the German population. The mean number of abortions was 3 (range 2-8).

RESULTS

Frequencies of the factor V Leiden mutation and the prothrombin G20210A mutation were equally high in the patient group compared with our control group (for factor V Leiden: 11/101 vs. 9/122; p-value: 0.348; for prothrombin G20210A: 2/101 vs. 3/122; p-value: 0.81). Moreover, in both the patient and control groups, 15 of the women were homozygous for the MTHFR C677T allele (15/101 vs. 15/122; p-value: 0.635). The occurrence of FV Leiden, FII and MTHFR mutations was not significantly increased in the patient group compared with our control group.

CONCLUSION

The results of the present study reveal no relationship between these common three thrombophilic mutations and recurrent abortions for the German population, and further studies are essentially recommended on whether a thrombophilia evaluation should be performed in patients with recurrent abortions.

Inherited Thrombophilia: Impact on Human Reproduction

The development of thrombotic disorders is a major threat for young women during pregnancy. It is one of the main causes of pregnancy-related disorders, which may also result in harm for the conceptus. Successful pregnancies require an even balance of coagulation and fibrinolysis, in order to secure stabilization of the basal plate as well as adequate placental perfusion. Thrombophilia is a laboratory definition for pre-disposing factors of thrombosis, which can be inherited or acquired. Many individuals, who carry a thrombotic defect remain asymptomatic, at least until additional boosting factors arise. The documentation of thrombophilic causes of recurrent miscarriage or pregnancy-related disorders is important, because of availability of effective early treatment. There is a rapidly growing awareness on the relationship of genetic factors influencing hemostasis and pregnancy-related disorders. The aim of our review is to summarize this knowledge, focusing on common genetic variations.

Inherited thrombophilia and poor pregnancy outcome

Gestational vascular complications are a major cause of maternal and fetal morbidity.A growing body of evidence suggests a significant role for inherited thrombophilia in the development of gestational vascular complications. While the majority of women with thrombophilia will have an uneventful gestation, case-control studies demonstrated that thrombophilia is more prevalent in cohorts of women with pregnancy loss and early-onset pre-eclampsia. Placental abruption and severe intrauterine growth restriction (IUGR) may also be associated with thrombophilia. Placental pathological findings in women with thrombophilia are hallmarked by thrombosis and fibrin deposition potentially to a greater degree than in normal pregnancy. Preliminary non-randomized studies suggest a benefit for prophylaxis with unfractionated and low-molecular-weight heparin (LMWH), and prospective randomized trials are in progress to define whether LMWH is effective in preventing pregnancy loss and other gestational vascular complications in women with thrombophilia and previous fetal wastage.

Inherited thrombophilia and pregnancy loss

A growing body of evidence obtained during the past 6 years suggests a significant role for inherited thrombophilia in the development of gestational vascular complications. Case-control and cross-sectional studies have demonstrated that thrombophilia is more prevalent in cohorts of women with pregnancy loss. Placental pathological findings in women with thrombophilia are hallmarked by thrombosis and fibrin deposition. Preliminary case-control studies suggest that low-molecular-weight heparins (LMWH) are effective in preventing pregnancy loss in women with thrombophilia and previous fetal wastage.

Thromboprophylaxis improves the live birth rate in women with consecutive recurrent miscarriages and hereditary thrombophilia

The effect of thromboprophylaxis with low molecular weight heparin (LMWH), on the subsequent live birth rate, in thrombophilic women with recurrent miscarriage has not been sufficiently assessed. The present study is a cohort study undertaken to assess the effect of enoxaparin on the subsequent live birth rate in women with hereditary thrombophila. Eighty-five patients with three or more consecutive pregnancy losses and a hereditary thrombophilia subsequently conceived. Thirty-seven were treated with daily subcutaneous injections of enoxaparin 40 mg and 48 were not treated. The outcome of the subsequent pregnancy was assessed in both groups of patients in terms of live births or repeat miscarriage. Forty-seven of the 85 patients were subsequently delivered, 38 have miscarried. Twenty-six of the 37 pregnancies in treated patients (70.2%) resulted in live births, compared with 21 of 48 (43.8%) in untreated patients (P < 0.02, OR 3.03, 95% CI 1.12-8.36). The beneficial effect was seen mainly in primary aborters, i.e. women with no previous live births (P < 0.008, OR 9.75, 95% CI 1.59-52.48). This benefit was also found in patients with a poor prognosis for a live birth (five or more miscarriages), where the live birth rate was increased from 18.2% to 61.6%. However, the benefit was not statistically significant, probably due to the small number of patients. If the beneficial effects of enoxaparin are confirmed by additional studies, thromboprophylaxis can be recommended for patients with hereditary thrombophilia and recurrent pregnancy loss.

Activated protein C resistance and pregnancy loss

Activated protein C resistance is a thrombophilia with an established role in producing thrombosis which more recently has been implicated in the pathogenesis of pregnancy loss. This review will analyse recent literature to evaluate this association and address the gestation and type of pregnancy loss.

Prevalence of factor V G1691A (factor V-Leiden) and prothrombin G20210A gene mutations in a recurrent miscarriage population

Factor V G1691A (FV-Leiden) and prothrombin G20210A mutations are major inherited risk factors for venous thrombosis. Recently, it was suggested that both mutations, through stimulation of venous and placental thrombosis events, were strongly associated with recurrent idiopathic miscarriages, although other studies disputed such a link. The aim of this study was to determine the prevalence of prothrombin G20210A and factor V G1691A (R506Q, FV-Leiden) mutations in women with recurrent idiopathic abortions and to recommend management for high-risk mutation carriers. One hundred ten women with two or more consecutive unexplained first-trimester miscarriages (mean age +/- SD, 32.3 +/- 5.3) were compared to 67 parous women with uncomplicated pregnancies (mean age +/- SD, 33.9 +/-7.3) (P = 0.134) from the same ethnic background. The presence or absence of the prothrombin G20210A and FV-Leiden mutations was assessed by PCR and RFLP analysis, using HindIII and MnlI digestion, respectively. In women with primary habitual abortion, 45 (40.91%) carried the FV-Leiden mutation, of whom 7 were in the homozygote and 38 were in the heterozygote states, and 15 (13.64%) carried the prothrombin G20210A mutation all as heterozygotes, compared to 16.42% and 2.99% carrier rates among controls, respectively, all of whom were heterozygote carriers. Of the other risk factors analyzed, smoking (OR 1.76; 95% CI = 0.79-3.94) was more prevalent in habitual aborters compared to controls. Both FV-Leiden and factor II G20210A mutations are major inherited risk factor associated with primary recurrent miscarriages. Women with a family or personal history of thrombosis should be screened before or early in the pregnancy for FV-Leiden and factor II G20210A mutations.

Thrombophilia and pregnancy loss

A large body of evidence obtained during the past 6 years suggests a significant role for inherited thrombophilia in the development of gestational vascular complications. While the majority of women with thrombophilia will have an uneventful gestation, case-control studies have demonstrated that thrombophilia is more prevalent in cohorts of women with pregnancy loss early onset preeclampsia, placental abruption, and severe intrauterine growth retardation (IUGR). Placental pathological findings in women with thrombophilia are hallmarked by thrombosis and fibrin deposition potentially to a greater degree than in normal pregnancy. Preliminary case-control studies suggest a benefit for prophylaxis with low molecular weight heparins (LMWH), and prospective randomized trials are in progress to define whether LMWH are effective in preventing pregnancy loss in women with thrombophilia and previous fetal wastage.

The design, execution, and interpretation of genetic association studies to decipher complex diseases

Genetic association studies are becoming increasingly frequent in the obstetric and gynecologic literature and they are considered central to the deciphering of the genetic basis of complex disease. The purpose, design, execution, analysis, and interpretation of genetic association studies in reproduction are discussed. Frequently used terms are defined (eg, genotype, haplotype, polymorphism, single nucleotide polymorphism, linkage disequilibrium). Guidelines are proposed for the evaluation of reports of genetic association studies (including selection of polymorphisms for study, study design, assay characteristics, sample size, multiple testing, and multivariable analysis). The potential value of this type of investigation in elucidating the mechanisms of disease in reproduction is illustrated.

Diagnostic studies for thrombophilia in women on hormonal therapy and during pregnancy, and in children

OBJECTIVE

To review the role of acquired and inherited prothrombotic risk factors that increase the risk of thrombosis in oral contraceptive users, during pregnancy, and in neonates, infants, and children; and to determine by the consensus opinion of recognized experts in the field which risk factors should be determined in which individuals at which time.

DATA SOURCES

Review of the medical literature and current clinical practice by a panel of experts in the field of thrombophilia.

DATA EXTRACTION AND SYNTHESIS

The experts made an extensive review of the published literature and prepared a draft manuscript, which included preliminary recommendations. The draft manuscript was circulated to participants in the College of American Pathologists Conference XXXVI: Diagnostic Issues in Thrombophilia prior to the conference. The manuscript and recommendations were then presented at the conference for discussion. Recommendations were accepted if a consensus of the 26 experts attending the conference was reached. The results of the discussion were used to revise the manuscript into its final form.

CONCLUSIONS

This report reviews the options for testing for thrombophilic states in women using oral contraceptives, during pregnancy, and in neonates and children. General guidelines for testing in these clinical situations are provided, along with citation of the appropriate supporting literature.

Clinical utility of factor V leiden (R506Q) testing for the diagnosis and management of thromboembolic disorders

OBJECTIVE

To review the current state of the art regarding the role of the clinical laboratory in diagnostic testing for the factor V Leiden (FVL) thrombophilic mutation (and other protein C resistance disorders), and to generate, through literature reviews and opinions of recognized thought-leaders, expert consensus recommendations on methodology and diagnostic, prognostic, and management issues pertaining to clinical FVL testing.

DATA SOURCES, EXTRACTION, AND SYNTHESIS

An initial thorough review of the medical literature and of current best clinical practices by a panel of 4 experts followed by a consensus conference review, editing, and ultimate approval by the majority of a panel of 28 additional coagulation laboratory experts.

CONCLUSIONS

Consensus recommendations were generated for topics of direct clinical relevance, including (1) defining those patients (and family members) who should (and should not) be tested for FVL; (2) defining the preferred FVL laboratory testing methods; and (3) defining the therapeutic, prophylactic, and management ramifications of FVL testing in affected individuals and their family members. As FVL is currently the most common recognized familial thrombophilia, it is hoped that these recommendations will assist laboratorians and clinicians caring for patients (and families) with this common mutation.

Hereditary thrombophilias are not associated with a decreased live birth rate in women with recurrent miscarriage

OBJECTIVE

To assesses the live birth rate without treatment in women with hereditary thrombophilia who have recurrent miscarriage and women without thrombophilia who have recurrent miscarriage.

DESIGN

Prospective observational study.

SETTING

Tertiary referral unit in university hospital.

PATIENT(S)

One hundred twenty women with thrombophilia and 65 women without thrombophilia.

MAIN OUTCOME MEASURE(S)

Number of live births or repeated miscarriages.

RESULTS

Of the 185 patients, 44 with thrombophilia and 26 without thrombophilia have conceived. Nineteen of the 44 pregnancies (43.2%) in thrombophilia patients have terminated in live births, compared with 8 of 26 pregnancies (30.8%) in patients without thrombophilia. This difference is not statistically significant.

CONCLUSIONS

Hereditary thrombophilia did not seem to affect the live birth rate in women with recurrent miscarriage.

Prevalence of genetic markers for thrombophilia in recurrent pregnancy loss

BACKGROUND

The genetic predispositions to venous thrombosis such as factor V Leiden (FVL) mutation (Arg 506 Gln), prothrombin (FII) gene mutation (G20210A), and mutation of the methylenetetrahydrofolate reductase (MTHFR) gene (C677T) have been reported to be associated with recurrent pregnancy loss. This paper examines the prevalence of markers for genetic thrombophilias in women with recurrent miscarriage.

METHODS

The prevalence of FVL, FII G20210A and MTHFR C677T was compared in 108 women with three or more pregnancy losses either exclusively in the first trimester, or mixed first and second trimester losses, with the prevalence found in 82 fertile parous control women without miscarriages. Markers for the thrombophilias were assessed by PCR analysis.

RESULTS

Twenty-three of the 108 patients (21.3%), had thrombophilia markers, which was similar to the proportion of patients in the control group (20.7%) with these markers. The prevalences of FVL and FII G20210A were lower in the study group than in the control group (3.7 versus 6.1% for FVL and 4.6 versus 6.1% for FII respectively); however, the difference was not statistically significant. In contrast, the prevalence of MTHFR C677T was higher in the study group than the control population (13 versus 8.5% respectively), but this difference was not statistically significant. There was no statistically significant prevalence of any particular thrombophilia in patients with previous first and second trimester pregnancy losses compared with patients with first trimester losses alone.

CONCLUSION

Thrombophilia was not found to be associated with recurrent pregnancy loss.

The absence of factor V Leiden mutation in Malays with recurrent spontaneous abortions

OBJECTIVES

The objectives of this study were to investigate the prevalence of factor V Leiden mutation in Malay women with recurrent spontaneous abortion and to clarify the contribution of the factor V Leiden mutation to recurrent miscarriages in these women.

DESIGN

A prospective case control study between June 1999 and April 2000.

SETTING

Hospital University Science of Malaysia, Kubang Kerian, Kelantan, and Maternal and Child Health Clinic, Pasir Mas, Kelantan, Malaysia.

SAMPLES

A total of 46 Malay women with a history of three or more first or second trimester miscarriages were studied. The control group consisted of 46 parous women without obstetric complications.

METHODS

Diagnosis of factor V Leiden mutation was made by examination of factor V Leiden allele product following Mnl I digestion of factor V Leiden alleles amplified by polymerase chain reaction.

RESULTS

None of the 46 women with recurrent spontaneous abortion carried the mutation. Also, we found no subject carrying the factor V Leiden alleles in the control group.

CONCLUSION

These results suggest that that there is no association between the factor V Leiden mutation and recurrent spontaneous abortion in the Malay population.