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Pharmacokinetics of Low Molecular Weight and Unfractionated Heparin in Pregnancy

This study has been completed.
University of British Columbia
Information provided by (Responsible Party):
University of Chicago Identifier:
First received: July 22, 2008
Last updated: October 31, 2016
Last verified: October 2016
To determine, through pharmacokinetic parameters, the ideal dosing protocol for dalteparin (a low molecular weight heparin) and unfractionated heparin for women desiring pregnancy who have evidence of an acquired (specifically, antiphospholipid syndrome) or inherited thrombophilia.

Recurrent Pregnancy Loss
Fetal Demise
Abortion, Habitual
Antiphospholipid Antibodies
Inherited Thrombophilia

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Pharmacokinetics of Low Molecular Weight and Unfractionated Heparin in Pregnancy

Resource links provided by NLM:

Further study details as provided by University of Chicago:

Primary Outcome Measures:
  • The best dosing strategy for either unfractionated or low molecular weight heparin will be the one exhibiting the best balance between a modified Akaike information criterion value, residual sum of squares, and coefficient of determination. [ Time Frame: Pre-pregnancy, 1st, 2nd, 3d Trimester and post-partum ]

Biospecimen Retention:   Samples Without DNA
Plasma from subjects to obtain concentrations of heparin will be retained

Enrollment: 14
Study Start Date: March 2005
Study Completion Date: July 2014
Primary Completion Date: January 2013 (Final data collection date for primary outcome measure)
Subjects opting for treatment with unfractionated heparin
Subjects opting for treatment with low molecular weight heparin

Detailed Description:

This study's specific objectives include:

  1. Evaluating pharmacokinetic (concentration-time) and pharmacodynamic (concentration- effect) parameters for dalteparin and UFH prior to pregnancy, during the 1st, 2nd and 3rd trimesters and postpartum, using revised dosing protocols based on previous study.
  2. Determining therapeutic response to the heparins, i.e. live birth rate and lack of maternal or fetal complications, in relation to drug exposure, based on AUC.
  3. Documenting maternal and fetal complications during pregnancy for dalteparin and UFH, using the revised dosing protocols.

Ages Eligible for Study:   18 Years to 44 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
The study population will consist of 15 subjects prescribed dalteparin and 15 subjects prescribed unfractionated heparin, who are identified through the University of Chicago Recurrent Pregnancy Loss Program.

Inclusion Criteria:

  • Two or more consecutive, otherwise unexplained miscarriages under 10 weeks of gestation, or, an otherwise unexplained intrauterine fetal demise of at least 10 weeks of gestation, and,
  • Persistently positive antiphospholipid antibodies, or, presence of Factor V Leiden, or, Prothrombin 20210A, or, antithrombin, protein S, or protein C deficiency, or, hyperhomocysteinemia associated with the methylenetetrahydrofolate reductase (MTHFR) polymorphism.

Exclusion Criteria:

  • Inability or refusal to give written informed consent.
  • Inability or refusal to self-administer heparin throughout pregnancy.
  • Hemoglobin value below 9.5 g/dL
  • Heparin use is contraindicated.
  • Renal disease.
  • Documented history of thrombosis.
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Please refer to this study by its identifier: NCT00721591

United States, Illinois
The University of Chicago
Chicago, Illinois, United States, 60637
Sponsors and Collaborators
University of Chicago
University of British Columbia
Principal Investigator: Mary D. Stephenson, MD, MSc University of Chicago
  More Information

Responsible Party: University of Chicago Identifier: NCT00721591     History of Changes
Other Study ID Numbers: 13677B
Study First Received: July 22, 2008
Last Updated: October 31, 2016

Keywords provided by University of Chicago:
Recurrent Pregnancy Loss
Habitual abortion
Fetal demise
Antiphospholipid antibodies
Inherited thrombophilia

Additional relevant MeSH terms:
Fetal Death
Abortion, Habitual
Pregnancy Complications
Pathologic Processes
Abortion, Spontaneous
Hematologic Diseases
Calcium heparin
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action processed this record on April 26, 2017