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
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.
- 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)
- 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.