Dose Adjusting Enoxaparin Thromboprophylaxis Dosage According to Anti-factor Xa Plasma Levels Improve Pregnancy Outcome

Study Overview
=================
Brief Summary
-----------------
The risk of venous thromboembolism increases in pregnancy. Thrombophilia whether genetic or acquired, is a hypercoagulable disorder that may increase the risk of venous thromboembolic events. Clinically, these events are presented as maternal deep vein thrombosis and pulmonary emboli. Thrombophilias are also associated with adverse fetal outcomes including intrauterine growth restriction, intrauterine fetal death, severe preeclampsia, placental abruption and recurrent abortions. Pregnant women who experienced one or more of the above complications are advised to be examined for the presence of the genetic or the acquired form of thrombophilia. Low molecular weight heparin prophylaxis, an anticoagulant, is advised for pregnant women with a history of thromboembolism, and many experts recommend prophylaxis for pregnant patients with a known thrombophilia and history of adverse pregnancy outcomes associated with these hypercoagulable states. Physiologic changes in normal pregnancy, including weight gain, increased renal clearance and volume of distribution, may decrease the availability of low molecular weight heparin (Enoxaparin or Dalteparin), or produce a less predictable response in pregnant women compared with nonpregnant women. There are no clear recommendations for use of prophylactic low molecular weight heparin in pregnancy. Clinicians tend to use doses suggested for nonpregnant patients. Regarding pregnant patients taking enoxaparin or dalteparin, the American College of Obstetricians and Gynecologists states that because of the lack of data regarding adequate dosing during pregnancy, anti-factor Xa levels may be monitored. Two recently published studies demonstrated that plasma anti-factor Xa levels during pregnancy were lower than expected, indicating that many pregnant patients may receive a subprophylactic dosing. Our objective is to check pregnancy outcome among thrombophilic women treated with an adjusted enoxaparin thromboprophylaxis dosage according to anti-factor Xa plasma levels compared to women with fixed dosage.

Official Title
-----------------
Dose Adjusting Enoxaparin Thromboprophylaxis Dosage According to Anti-factor Xa Plasma Levels Improve Pregnancy Outcome

Conditions
-----------------
Fetal Demise, Fetal Growth Restriction, Preeclampsia, Abruptio Placentae, Thromboembolism

Intervention / Treatment
-----------------
* Drug: enoxaparin


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: WOMEN WITH Singleton gestation A history of fetal demise, fetal growth restriction, placental abruption, preeclampsia, recurrent abortions or maternal thromboembolic event. Acquired or congenital thrombophilia treated with low molecular weight heparin Exclusion Criteria: Women treated empirically with low molecular weight heparin Women with a history of pregestational diabetes. Significant polyhydramnios or oligohydramnios, major fetal structural, generic or chromosomal malformations

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: enoxaparin fixed<br>enoxaparin dosage will be fixed during pregnancy | |
| Experimental: enoxaparin adjusted<br>enoxaparin dosage will be adjusted according to anti-factor Xa plasma levels | Drug: enoxaparin<br>* enoxaparin dosage will be adjusted according to anti-factor Xa plasma levels<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| placental syndrome or thromboembolic event |  | 9 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| enoxaparin side effects |  | 9 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
placental syndrome, maternal thromboembolic event, enoxaparin, anti-factor Xa