Inherited Thrombophilia: Treatment during Pregnancy

The Proper Diagnosis of Thrombophilic Status in Preventing Fetal Growth Restriction

Fetal growth restriction is an important part of monitoring a pregnancy. Because guidelines or diagnostic criteria for either minor or major thrombophilia are scarce, this systematic review aims to summarize the present knowledge in the field. We performed the CRD42022376006 protocol in Prospero with a systematic literature search in PubMed and Web of Science databases and included original full-text articles (randomized control trials and clinical trials) from the last 10 years, published in English, and with the "thrombophilia AND (pregnancy OR diagnostic criteria) AND fetal growth restriction" criteria. After two researchers extracted the articles of interest, they were assessed using the Newcastle-Ottawa Scale and eight articles were included. The elements from the thrombophilia diagnostic predict IUGR, factor V Leiden mutation, MTHFR C667T mutation, protein S deficiency, antithrombin deficiency, factor VII polymorphism, and antiphospholipid antibodies, while the association of protein C, PAI-1 and certain combinations of mutations are still under debate and require the collection of more data. The present systematic review provides an extensive picture of the actual knowledge about thrombophilia diagnosis and its links with pregnancy complications, such as intrauterine growth restriction, despite its limitation in the inclusion of other actually debated disorders such as PAI-1 mutation, protein C deficiency and other thrombophilia types.

Association between prophylactic low-molecular-weight heparin use in pregnancy and macrosomia: analysis of the Ottawa and Kingston birth cohort

Essentials Low-molecular-weight heparin (LMWH) is used to prevent venous thromboembolism (VTE) in pregnancy. We evaluated the association between LMWH and large for gestational age (LGA) infants. We found no significant associations between LMWH use and LGA. LMWH does not appear to increase the risk for the delivery of an LGA infant. SUMMARY: Background Low-molecular-weight heparin (LMWH), an anticoagulant, is the recommended drug for thromboprophylaxis and treatment of venous thromboembolism (VTE) in pregnancy. During pregnancy, LMWH is routinely prescribed to mothers with an increased risk of VTE or with a history of thrombosis. Although clinical reports of larger offspring born to women administered LMWH have been noted, no studies to date have evaluated or associated the use of LMWH and large for gestational age (LGA) infants. Objectives To determine whether there is an association between LMWH usage in mothers and the prevalence of LGA. Patients/Methods We performed an analysis of the Ottawa and Kingston (OaK) Birth Cohort and report characteristics of LMWH and association LGA (> 10%ile). We used coarsened exact matching (CEM) methods to account for bias and confounding. Results A total of 7519 women from the OaK Birth Cohort were included; 59 were administered LMWH during pregnancy (0.78%). Mothers prescribed LMWH had significantly greater BMI (P = 0.0001), age (P = 0.0001) and parity (P = 0.02). Gestational length was shorter among women administered LMWH compared to those without treatment (37.7 ± 2.0 vs. 39.2 ± 2.0, P < 0.0001), an iatrogenic finding. The odds ratio of an LGA delivery among women administered LMWH was 1.02 (95% confidence interval [CI], 0.48-2.16; P = 0.96) in unadjusted analyses and was 1.15 (95% CI, 0.49-2.71) in the matched sample adjusted for maternal age, BMI and gestational age. Conclusions These results, although exploratory, provide indirect evidence of no increased risk of LGA infants among women prescribed LMWH.

Facteurs génétiques à prendre en considération dans le cadre de l'examen gynécologique annuel

OBJECTIF

Offrir aux médecins un survol des troubles génétiques courants qui devraient être pris en considération dans le cadre de l'examen gynécologique annuel d'une patiente, et ce, afin de déterminer le risque que court celle-ci ou d'en venir à procéder à des examens particuliers ou à orienter la patiente vers un autre service de sous-spécialité, en fonction de ses antécédents personnels ou familiaux.

OPTIONS

Ces renseignements d'ordre génétique peuvent être utilisés aux fins de la sensibilisation des patientes et du dépistage ou du diagnostic de possibles maladies et/ou mutations.

ISSUES

L'utilisation de ces renseignements d'ordre génétique pourrait mener à l'amélioration de l'évaluation des risques et des avantages et à celle de la prise en charge dans le cadre de l'examen gynécologique annuel. RéSULTATS: Les études publiées en anglais, jusques et y compris en mai 2010, ont été récupérées par l'intermédiaire de recherches menées dans PubMed et la Cochrane Library au moyen d'un vocabulaire contrôlé (« gynaecological diagnosis », « genetic inheritance ») et de mots clés (« genetic risk », « genetic mutation », « inheritance », « family history », « uterus », « ovary », « endometrial », « vagina », « colon », « gastric », « renal », « breast », « cardiac », « thrombophilia », « diabetes », « epilepsy », « leiomyomata uteri ») appropriés. D'autres sources ont été identifiées par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales.

VALEURS

Le niveau des résultats ne permet pas la formulation de recommandations factuelles. AVANTAGES, DéSAVANTAGES ET COûTS: La présente opinion de comité améliorera l'utilisation de nouvelles connaissances génétiques et leur application aux soins gynécologiques offerts annuellement aux femmes. Les occasions de gestion du risque et de diagnostic, pour ce qui est des troubles gynécologiques génétiques, s'en trouveront améliorées. Une compréhension plus exhaustive des troubles génétiques pourrait entraîner une hausse de l'anxiété et du stress psychologique chez les femmes et les membres de leur famille.

COMMANDITAIRE

Société des obstétriciens et gynécologues du Canada.

RECOMMANDATIONS

Le niveau des résultats ne permet pas la formulation de recommandations factuelles.

Effects of anticoagulant therapy on pregnancy outcomes in patients with thrombophilia and previous poor obstetric history

This study investigates the effects of anticoagulant therapy on pregnancy outcomes in 204 patients with thrombophilia and previous poor obstetric outcomes. Patients with poor obstetric history (pre-eclampsia, intrauterine growth retardation, fetal death, placental abruption, recurrent pregnancy loss) and having hereditary thrombophilia were included in this study. Poor obstetric outcomes were observed more frequently in patients who had not taken anticogulant therapy compared with treated group. Live birth rate, gestational age at birth and Apgar scores were significantly higher in the treated group when compared with the untreated group. There were no significant differences in terms of birthweight, mode of delivery and admission rates to the neonatal intensive care unit (NICU). Low-molecular-weight heparin (LMWH) plus acetylsalicylic acid (ASA) had higher gestational age at birth, Apgar scores, live birth rate and a lower abortion rates when compared with controls; in contrast, no significant difference was observed in terms of birthweight, mode of delivery, obstetric complications and admission rates to NICU. There were no significant differences between control group and both LMWH only and ASA only groups in terms of gestational age at birth, Apgar scores, birthweight, mode of delivery, obstetric complications and admission rates to NICU. Only LMWH group had higher live birth rate as compared with control group. The use of only ASA did not seem to affect the perinatal complication rates and outcomes. In conclusion, anticoagulant therapy with both LMWH and ASA seems to provide better obstetric outcomes in pregnant women with thrombophilia and previous poor obstetric outcomes.

Low molecular weight heparin treatment and impact of inherited thrombophilia type in pregnancies with previous adverse outcome

OBJECTIVE

To assess the impact of low molecular weight heparin (LMWH) treatment in 50 pregnancies of women with inherited thrombophilia and adverse pregnancy outcome (APO) in previous untreated pregnancies. The impact of "Conventional" (FVL, PT, AT, PC, PS) and "Novel" (MTHFR, PAI-1, ACE) thrombophilias on APO was investigated.

METHODS

The primary outcomes (PO) were: early and late pregnancy loss (EPL, LPL), preterm birth (PTB) or term birth (TB) compared to the last untreated pregnancies of the same women. Secondary outcomes (SO) were APO in LMWH treated and last untreated pregnancies ended with birth. PO and SO were compared in relation to the thrombophilia type.

RESULTS

LMWH decreased EPL and LPL rate and improved TB rate compared with last untreated pregnancies (p < 0.001). There were less PTB (p = 0.019) and no cases of intrauterine fetal death (IUFD) (p = 0.0019) in LWMH-treated pregnancies. The division to Conventional and Novel thrombophilias showed: (a) difference between pregnancy losses and birth rate (p = 0.0069) and (b) no difference in the prevalence of APO in untreated pregnancies ended with birth.

CONCLUSIONS

LMWH treatment improves pregnancy outcome in women with inherited thrombophilia and APO in previous pregnancies. Novel thrombophilias have the equal impact on the pregnancy outcome compared to the Conventional thrombophilias.

Genetic considerations for a woman's annual gynaecological examination

OBJECTIVE

To provide the physician with an overview of common genetic conditions that should be considered during a women's annual gynaecological assessment to determine the patient's risk or to initiate specific testing or referral to another subspecialty service, depending on personal or family history.

OPTIONS

This genetic information can be used for patient education and possible disease and/or mutation screening or diagnosis.

OUTCOMES

The use of this genetic information may allow improved risk-benefit assessment and management at the annual gynaecological examination.

EVIDENCE

Studies published in English up to and including May 2010 were retrieved through searches of PubMed and the Cochrane Library, using appropriate controlled vocabulary (gynaecological diagnosis, genetic inheritance) and key words (genetic risk, genetic mutation, inheritance, family history, uterus, ovary, endometrial, vagina, colon, gastric, renal, breast, cardiac, thrombophilia, diabetes, epilepsy, leiomyomata uteri). Other literature sources were identified through searching the web sites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The levels of evidence are not adequate for evidence-based recommendations to be made.

BENEFITS, HARMS, AND COSTS

This committee opinion will enhance the use of new genetic knowledge and its application to the annual gynaecological care of women. Risk management and diagnostic opportunities for genetic gynaecological conditions will be improved. A more complete understanding of genetic conditions may increase anxiety and psychological stress for women and their families.

SPONSORS

Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

The levels of evidence are not adequate for evidence-based recommendations to be made.

A retrospective analysis of fondaparinux versus enoxaparin treatment in women with infertility or pregnancy loss

PROBLEM

We compared the pregnancy success rates and safety parameters of fondaparinux versus enoxaparin, combined with immunotherapy, in patients with a history of miscarriage and/or infertility and coagulant defects.

METHOD OF STUDY

A total of 127 pregnancies in 110 patients with a history of miscarriage and/or infertility were retrospectively evaluated. Of these, 29 pregnancies used fondaparinux 2.5 mg daily and 98 pregnancies used enoxaparin 30 mg twice daily.

RESULTS

The pregnancy success rate was 59% (17/29; 95% CI, 41-75%) for patients receiving fondaparinux and 58% (57/98; 95% CI, 48-68%) for patients receiving enoxaparin. No difference was detected in birth weight (2.7 +/- 0.8 and 2.9 +/- 0.6 kg, respectively) or gestational age at delivery (37.3 +/- 2.2 and 37.7 +/- 2.1 weeks, respectively). No birth defects, severe bleeding-related complications, or serious allergic reactions were observed.

CONCLUSION

In patients with a history of miscarriage, infertility, and coagulant defects receiving immunotherapy, fondaparinux resulted in successful pregnancy outcomes comparable with enoxaparin therapy. Although no difference in outcome was observed in our analysis, a much larger study is required to achieve statistical power.

Independent risk factors for cesarean section among women with thrombophilia

OBJECTIVE To determine the prevalence of cesarean section (CS) in pregnant women with a diagnosis of thrombophilia and to identify risk factors for CS.

STUDY DESIGN

The women were recognized by an ICD-9 code from a computerized database. Maternal records were reviewed between the years 2000 and 2005. Pregnancy characteristics of 86 women with thrombophilia were compared according to the mode of delivery: CS (n = 18) versus vaginal delivery (n = 68).

RESULTS

The prevalence of CS in the study population was 21% (18/86). Women with CS had a lower gestational age at delivery (P = 0.019), lower birth weight (P = 0.048), higher incidence of the following: preterm delivery (P < 0.001), gestational hypertension (P = 0.028), intrauterine growth retardation/antepartum death/placental abruption (P = 0.065) and non-reassuring fetal heart rate (NRFHR) monitoring (P < 0.001) compared to those with vaginal delivery. In a multiple logistic regression analysis only NRFHR monitoring, birth weight and malpresentation remained statistically significant.

CONCLUSION

CS in women with thrombophilia are associated with common obstetrical causes rather than specific thrombophilia dependent factors.

Preventing thrombophilia-related complications of pregnancy

Pregnancy is associated with an increased risk of venous thromboembolism (VTE) and approximately half of all pregnancy-related VTEs are associated with thrombophilia. Recent studies suggest that there is a link between thrombophilia and other adverse pregnancy outcomes, such as fetal loss, preeclampsia, placental abruption and intrauterine growth restriction. However, the associations reported are modest, and high quality data are limited. Although the most compelling data derive from pregnant women with antiphospholipid antibodies, the use of anticoagulants for the prevention of pregnancy complications other than VTE in women with heritable thrombophilias is becoming more frequent. In this article, we review the impact of the various thrombophilias on pregnancy and its outcome, the evidence for therapies aimed at prevention of thrombophilia-related pregnancy complications, and briefly discuss the role of screening for thrombophilia in pregnancy.

Enoxaparin-metformin and enoxaparin alone may safely reduce pregnancy loss

Polycystic ovary syndrome (PCOS), thrombophilia, and hypofibrinolysis are associated with recurrent pregnancy loss (RPL) and spontaneous abortion (SAB). In 28 Caucasian women, 21 women with PCOS (4 with previous thrombosis, 18 with 1 SAB or more, and 20 with 1 coagulation disorder or more), and 7 women with coagulation disorders-thrombi, we speculated that prospective treatment with enoxaparin-metformin or enoxaparin alone would successfully and safely promote healthy live births compared with previous untreated pregnancies. In 21 women with PCOS, metformin (1.5-2.55 g/day) was given before and during pregnancy with concurrent enoxaparin (60 mg/day). Of 21 PCOS women, 19 women had 40 previous untreated pregnancies, 7 had live births (18%), 3 had elective abortions (ABs) (8%), and 30 had SABs (75%). On enoxaparin-metformin, these 19 women had 24 pregnancies, 20 live births (83%), and 4 SABs (17%); the SAB rate was 4.4-fold lower than previous untreated pregnancies (McNemar's s = 20.8, P < 0. 0001). Two women with PCOS without previous pregnancies, but with previous thrombosis, had 2 pregnancies on enoxaparin-metformin and 2 live births. Of the 7 women with coagulation disorders-thrombi, 4 had 15 previous pregnancies without enoxaparin, with 6 live births (40%), 8 SABs (53%), and 1 elective AB (7%). On enoxaparin, these 4 women had 4 pregnancies, with 4 (100%) live births (McNemar's s = 8.0, P = 0.005). The other 3 women with coagulation disorders-thrombi had 4 pregnancies on enoxaparin with 4 live births. No adverse maternal-fetal side effects were reported on enoxaparin alone or enoxaparin-metformin. Enoxaparin-metformin reduces pregnancy loss in women with PCOS-coagulation disorders and in women with coagulation disorders-thrombi.

A descriptive evaluation of unfractionated heparin use during pregnancy

BACKGROUND

The mainstay of oral anticoagulant therapy, warfarin sodium, crosses the placenta during pregnancy and may cause fetal complications. Unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) do not cross the placenta and have demonstrated utility in the prevention and treatment of thrombosis during pregnancy.

OBJECTIVES

The purpose of this study was to review treatment strategy, indication, and maternal and fetal outcomes in anticoagulated pregnancies at Kaiser Permanente Colorado.

PATIENTS/METHODS

We identified 103 pregnancies in 93 mothers prescribed an anticoagulant during a pregnancy occurring between January 1, 1998 and March 31, 2005.

RESULTS

The majority of patients were treated with UFH (89.3%). Indications for anticoagulation included venous thromboembolism (VTE) prophylaxis (53.4%), history of pregnancy loss (29.1%), acute VTE (16.5%), and history of cerebral vascular accident (CVA) (1.0%). There were no maternal deaths. Fetal demise occurred in 8 pregnancies (7.8%) at a median 14 weeks gestation (range 7-22 weeks). No fetal demise occurred in pregnancies treated for acute VTE or history of CVA. There were two occurrences of pulmonary embolism (1.9%) and two hemorrhagic events requiring transfusion (1.9%).

CONCLUSIONS

Maternal and fetal adverse events were infrequent in our population of anticoagulated pregnancies. UFH remains a viable option among more expensive LMWH products.

Anticoagulant therapy and thromboprophylaxis in patients with thrombophilia

OBJECTIVE

The aim of this review was to discuss the effectiveness of anticoagulant therapy and thromboprophylaxis in patients with thrombophilia.

METHODS

A MEDLINE search was performed using the keywords: "anticoagulant therapy", "pregnancy", "thromboprophylaxis", "thrombophilia", "adverse pregnancy outcomes", "venous thromboembolism", "heparin" and "low molecular weight heparin".

RESULTS

The identification of a link between thrombophilic factors and adverse pregnancy outcome offers treatment possibilities. Until recently, it has not been clear whether antithrombotic therapy is useful in women with previous placental dysfunction and inherited thrombophilia. Anticoagulant therapy is indicated during pregnancy for the prevention and treatment of venous thromboembolism, for the prevention and treatment of systemic embolism in patients with mechanical heart valves and, for the prevention of pregnancy complications in women with antiphospholipid antibody syndrome or other thrombophilic disorders and previous pregnancy complications. At present, limited data exist regarding the efficacy of anticoagulants during pregnancy. Recommendations are largely based on data extrapolated from non-pregnant patients, case reports, and case series of pregnant patients. Many physicians have been treating such women with antithrombotic therapy on the basis of logic and anecdotal evidence.

CONCLUSION

A regimen for thrombophylaxis and treatment of thrombophilic parturient based on thrombophilia type is proposed.

Inhibition of extrinsic hemostasis activation by low-molecular-weight heparin

Low-molecular-weight heparins (LMWHs) are very important drugs; unfortunately, the routine global hemostasis assays activated partial thromboplastin time and prothrombin time are not sensitive to LMWHs. Here the 50% inhibitory concentration (IC(50)) values of heparin and LMWHs on extrinsic thrombin generation are determined. Pooled normal plasma was supplemented with 0-2 IU/ml unfractionated heparin, 0-2 IU/ml LMWH dalteparin, or 0-20 microg/ml pentosanpolysulfate in 5-ml polystyrole tubes (23 degrees C) and tested in the tissue-factor-triggered extrinsic coagulation activity assay (EXCA): 50 microl plasma + 5 microl tissue factor/CaCl(2), 1 and 2 min incubation time at 37 degrees C (coagulation reaction time for EXCA-1 and EXCA-2); + 100 microl of 2.5 mol/l arginine (pH 8.6), 20 min at room temperature; + 50 microl of 1 mmol/l CHG-Ala-Arg-pNA, 1.25 mol/l arginine; increase in absorbance/time at 23 degrees C; calibrator = 1 IU/ml bovine thrombin in 6.7% human albumin replacing the plasma sample; in EXCA-1, about 1 IU/ml thrombin is generated in pooled unfrozen normal citrated plasma. The IC(50) values in EXCA-1 are 0.1 IU/ml heparin, 0.02 IU/ml LMWH, and 4.7 microg/ml pentosanpolysulfate. In ECXA-2 the IC(50) values are 0.07 IU/ml, 0.01 IU/ml, and 4.6 microg/ml, respectively. The EXCA reflects the efficiency of anticoagulants on plasmatic coagulation. It is suggested to adjust the dosage of LMWH according to the EXCA value; about 30% of normal extrinsic thrombin generation might be the correct dose for prophylactic anticoagulation.