1. Inherited Thrombophilia is Associated with:
Recurrent pregnancy losses
Preeclampsia
Intrauterine growth retardation
Stillbirths
Preterm labors
Maternal deaths

2. Recurrent Miscarriage Predisposes Women to:
Preterm labor
Intrauterine growth retardation
Preeclampsia
Fetal anomalies

3. New Actions of Antiphospholipid Antibodies
Cause increased serum tumor necrosis factor (TNF) alpha
Alters the TH1:TH2 balance towards TH1
Decreases interleukin-3 (IL-3)
TNF alpha can initiate the release of tissue factor and initiate the clotting cascade

4. Inherited Thrombophilias
Rey et al. in a meta-analysis found:
Increased incidence of factor V Leiden mutation
Prothrombin gene mutation factor II
MTHFR gene mutation in patients with recurrent miscarriage
Screening for inherited thrombophilia in women with recurrent spontaneous abortion (RSA), infertility and implantation failure is indicated

5. Heparins 1
Heparin increases serum TNF binding protein protecting against harmful systemic manifestations
Low molecular weight (LMW) heparins inhibit TNF alpha production
Heparin and LMW heparin are antiinflammatory

6. Heparins 2 LMW heparin limits neutrophil extravasion
LMW heparin decreases vein wall permeabiolity
Prevents accumulation of proliferating vascular smooth muscle that encroaches on the lumen of arteries

7. Inherited and Acquired Thrombophilia
Pregnancy is a hypercoagulable state (Stirling et al., 1984)
Antiphospholipid antibodies (aPL), an acquired thrombophilic defect, are an important and treatable cause for pregnancy losses at all gestational ages (Rai et al., 1997)
Inherited thrombophilias are a greater cause for pregnancy losses and complications at all gestational ages (Rai et al., 2002)

8. Factor V Leiden and RSA Outcome of Untreated Pregnancies
Early Losses FVL +
37.5% -
69.3%
Late Losses FVL
11.1%
48.9%

9. Factor V Leiden Treatment
Increase LMW heparin to twice daily with a positive pregnancy test
LMW Heparin 30 or 40 mg once daily started on cycle day 6
Continue until 6 weeks postpartum
Aspirin 81 mg daily starting cycle day one of conception cycle

10. Factor V Leiden Outcome with Treatment on RSA Women
Carp et al., 2002
Without treatment
33.2%
With treatment
85.7%

11. Recommended Tests LAC screen APTT and dRVVT
Antiphospholipid antibodies
Factor V Leiden gene mutation
Prothrombin gene factor II gene mutation
Methylenetetrahydrofolate reductase (MTHFR) gene mutation
Antinuclear Antibody (ANA)

12. Importance of ANA Testing Infertility, RSA
Ogasawara et al., 1999
25% of RSA patients have low titer positive ANA with speckled pattern
21% of Infertility patients have low titer positive ANA with speckled pattern
A positive ANA mandates a full immunological workup

13. Mechanisms of Thrombosis
Protein C and S and AT III slow down the forward momentum of clot formation
Factor V Leiden is a mutated variant of factor V that is partially resistant to inactivation by activated protein C

14. Mechanisms of Thrombosis in Placenta Antibodies
Stern et al., 1998
Increased localization of prothrombotic proteins
Blocking of natural anticoagulants
Transmembrane signaling

15. Treatment for MTHFR Hetero and Homozygous Women
Folgard RXTM 2.2 daily (lifetime)
Aspirin 81 mg daily (lifetime)
LMW heparin 30 – 40 mg daily, cycle day 6, increasing to twice daily until 6 weeks postpartum

16. Treatment of Prothrombin Gene Factor II Variant
Aspirin 81 mg daily
LMW heparin 30 – 40 mg daily, cycle day 6, increasing to twice daily until 6 weeks postpartum

17. MTHFR Outcome with and Without Treatment
Carp et al., 2004
With treatment
66.7%
Without treatment
3.5%

18. Different direction in intact vessels...
Vessel Wound
Factor VII+ Tissue Factor
Coagulation Cascade
Thrombin
Factors V and VIII
Fibrinogen ® Fibrin
Platelets
Activated Factors V and VIII (Va and VIIIa)
Further Coagulation Activation
Different direction in intact vessels...

19. Intact Blood Vessel Thrombin + Thrombomodulin (Endothelial Surface)
Protein C System Activation
Activated C (APC) and Protein S and Factor V
Deactivation of Va & VIIIa
Normal conditions ® Anticoagulant mechanisms ® Procoagulant mechanisms
Wound conditions ® Procoagulant mechanisms ® Anticoagulant mechanisms

20. European Prospective Cohort on Thrombophilia (Lancet 1996)
Pregnancies
Fetal
Loss
Stillbirth/
Miscarriage
Stillbirth,
Combined
Defects
Factor V Leiden
Thrombophilia
(n=843)
n=1524
1.35
3.6
14.3 2
Control
(n=541)
n=1019 1

21. Missense Mutation G to A in the FV Gene
Position 1691, leading to Arg506Gln protein (factor V Leiden)
Most frequent genetic defect associated with disease
In Europe 3-7% with APC-R, 1% homozygotes
“Mitera” study: 4.5% carriers (Greek blood donors)

22. Hypercoagulability has Positive Genetic (Natural) Selection Effects
In the past ® survival advantage (war and hunting wounds, deliveries)
Now ® artifacts of modern life style

23. Mutated Factor Va (FV Leiden) ® Less Sensitive to APC Deactivation
APC-Resistance ® frequent to general population, 3-5%
Carriers have an increased risk for thromboses
Most important factor of venous thromboembolism
More than half of the patients with hereditary thrombophilia

24. 8.9% 4.2% 30% 20% 0.9% 10% 3% 4.1% FV Leiden Subjects No Mutation
Severe
Pre-eclampsia
Normotensive
Women on
Oral Contraception and Thromboses
Oral Contraception and Cerebral-Vein Thromboses
Stroke in Young Women
FV Leiden Subjects
8.9%
4.2%
30%
20%
0.9%
No Mutation
10% 3%
4.1%
Domna S. Dizon-Townson et al, Salt Lake City, Utah, Am J Obstet Gynecol, 1996
Margareta Hellgren et al, Mohndal and Malmo, Sweden, Am J Obstet Gynecol, 1994
Longstreth WT Jr et al, Washington, Seattle, Stroke, 1998
Martinelli I et al, Milan, N Engl J Med, 1998

25. First Trimester Abortions
Br J Haematol, 1997 Brenner B et al., Bruce Rappaport Faculty of Medicine, Haifa, Israel
Women with Fetal Losses (n=39)
Pregnancies
First Trimester Abortions
Late Abortions
Intrauterine Death
Live Births
FV Leiden (n=19)
128
50%
17%
47%
18%
With APC-R (n=9) 56

26. Prothrombin Gene G20210A Variant
Inherited in an autosomal dominant manner
Gene on chromosome 11p11-q12 (21kb, 14 exons) encodes a plasma glycoprotein, activated to thrombin by FXa and Fva
Point mutation G20210A in the 3' untranslated region is associated with elevated prothrombin levels

27. Title Needed??? Accounts for ~18% of inherited thrombophilia
Accounts for ~6% of unselected patients with deep-vein thrombosis
Frequently co-inherited with other genetic risk factors like factor V Leiden

28. Title Needed???
Carriers have a 2 to 5 fold increased risk of venous thrombosis, including cerebral-vein thrombosis
Carriers using oral contraceptives have a highly elevated risk of cerebral-vein thrombosis

29. 5.1 20% 1.9% 1.6 3% 1.6% Prothrombin Gene Variant Subjects No Mutation
Women with Myocardial Infarction
Women on Oral Contraception and Cerebral-Vein Thromboses
Stroke in Young Women
Prothrombin Gene Variant Subjects
5.1
20%
1.9%
No Mutation
1.6 3%
1.6%
Longstreth WT Jr et al., Washington, Seattle, Stroke, 1998
Rosendaal FR et al., Leiden, Netherlands, Blood, 1997
Martinelli I et al., Milan, N Engl J Med, 1998

30. Title Needed??? Carrier frequency of 1 to 4% in different populations
Carrier frequency in southern Europe is nearly twice
As high as in northern Europe
"Mitera" study: 3.8 % among healthy Greek blood donors
Geographical distribution probably due to founder effect

31. Hyperhomocysteinemia
Cystathionine ß-synthase (CBS) deficiency causes the metabolic disorder "homocystinuria" (including premature arteriosclerosis and thrombosis)
MTHFR deficiency is an inborn error of folate metabolism (with increased risk of arteriosclerosis and thrombosis)

32. Hyperhomocysteinemia (Cont.)
Mild hyperhomocysteinemia has been recognized as a risk factor for arteriosclerosis and thrombosis
Mild hyperhomocysteinemia due to a thermolabile variant of the MTHFR enzyme has been associated with premature vascular disease
Homocysteine is presumed to damage the endothelial cell, but the exact mechanism of its toxicity is unknown

33. Title Needed???
Homozygous individuals show reduced MTHFR activity, increased thermolability and hyperhomocysteinemia
Homozygotes may have an increased risk of cardiovascular disease and neural tube defects

34. Title Needed???
Relatively high frequency throughout the world: allele frequency from 6% in Africa to 40% in some European populations
Selective advantage to explain high frequency

35. 25% 8% 38% Women with Mild Hyperhomocysteinemia
Placental Abruption
(n=31)
Intrauterine Fetal Death (n=18)
Small for Gestational Age Infants (n=13)
Women with Mild Hyperhomocysteinemia
25% 8%
38%
J. I. P. de Vries et al., Amsterdam British Journal of Obstetrics and Gynaecology, 1997

36. “Mitera” Study, ASH 1998 Haematology Dept, Haemostasis Lab
Group
Aborters > 2, (n=37)
Non-Aborters, (n=102)
Age Median (range)
34 (19-51)
34 (20-54)
Platelets
All Normal PT
INR
APTT
Fibrinogen > 400 mg/dl
30%, n=11
14%, n=14
Fibrinogen < 400 mg/dl
70%, n=26
86%, n=88
LA Positive (by confirmative test)
16%, n=16
9%, n=9
AT III < 75%
3%, n=1
3%, n=3
PC < 75%
PS < 75%
Unreliable Test
Increased APC-R (suggesting FV Leiden)
22%, n=8
11%, n=11

37. Consultation Extended family screening
Anticoagulant prophylaxis in selected cases
Inherited Thrombophilia (Prothrombotic Gene Mutation)
Acquired Thrombophilia
Hypercoagulability
Thrombosis

38. LMW Heparin
Given subcutaneously to maintain trough anti-Xa activity of U/ml and 2 h post injection levels of U/ml
Checking of levels are no longer recommended
May check monthly during pregnancy

39. LMW Heparin Complications
Epidural anesthesia is managed by omitting a dose or inserting the needle 6 hours after the previous dose
There were no thromboembolic events or excessive hemorrhages
There is one report of osteoporotic vertebral collapse post partum
Hunt BJ et al., 1997

40. LMW Heparin Complications
No local or systemic side effects reported
No excessive intrapartum or postpartum bleeding in vaginally or c-sectioned delivered patients
Epidural was done without complications
No intraventricular hemorrhages in any infant
No effect on platelet count
Dulitzke M. et al., 1996