Successful pregnancy outcome in women with bad obstetric history and recurrent fetal loss due to thrombophilia: effect of unfractionated heparin and low-molecular weight heparin

Clin Appl Thromb Hemost. 2008 Apr;14(2):174-9. doi: 10.1177/1076029607306400. Epub 2007 Dec 26.


Acquired and inherited thrombophilias are known to be associated with unfavorable pregnancy outcome including recurrent fetal loss. There are differences of opinion whether these patients need to be treated with aspirin, unfractionated heparin, low-molecular weight heparin, corticosteroids, or intravenous immunoglobulins. In all, 25 consecutive patients with a history of fetal loss and 7 patients who presented in early pregnancy with deep-vein thrombosis were treated, and their pregnancy outcome was noted. All the women were positive either for a solitary or for a combination of acquired and heritable thrombophilia markers. In all, 23 patients were treated with unfractionated heparin and 9 with low-molecular weight heparin. In all, 16 out of 23 patients (69.6%) treated with unfractionated heparin and 9 out of 9 (100%) treated with low-molecular weight heparin had successful pregnancy outcome. There was a complete resolution of thrombus in all the cases. None of the patients had any adverse reactions such as heparin-induced thrombocytopenia, thrombosis, or fracture. Both unfractionated heparin and low-molecular weight heparin were effective in cases of bad obstetric history and recurrent pregnancy loss due to thrombophilia. However, low-molecular weight heparin was found to be more effective than unfractionated heparin along with other advantages of not requiring laboratory monitoring and easy administration. None of the patients in either group had to interrupt the therapy for any adverse treatment-related complications.

MeSH terms

  • Abortion, Habitual / prevention & control*
  • Adult
  • Anticoagulants / therapeutic use*
  • Female
  • Heparin / therapeutic use*
  • Heparin, Low-Molecular-Weight / therapeutic use*
  • Humans
  • Infant, Newborn
  • Pregnancy
  • Pregnancy Complications, Hematologic / drug therapy*
  • Pregnancy Outcome*
  • Thrombophilia / drug therapy*
  • Venous Thrombosis / drug therapy


  • Anticoagulants
  • Heparin, Low-Molecular-Weight
  • Heparin