• Heparin;
  • antiphospholipid antibodies;
  • recurrent pregnancy loss;
  • autoantibodies;
  • miscarriage

PROBLEM: To determine if heparin may act directly with antiphospholipid antibodies (APA) to prevent recurrent pregnancy loss (RPL).

METHOD: Patients were seen at the University of Texas Southwestern Medical Center. Twenty women with a history of RPL (≥3 miscarriages), positive APA, and an otherwise normal evaluation were treated with heparin in two daily subcutaneous dosages during a successful pregnancy. APA levels were obtained prior to conception and again at 6, 20, and 30 weeks.

RESULTS: Heparin reduced APA binding to cardiolipin and phosphatidylserine in a dose-dependent fashion in ELISA. Heparin affinity chromatography absorbed over 80% of the IgG anticardiolipin antibody in serum from women with high levels of APA. Women treated with increasing dosages of heparin during pregnancy had inversely decreasing levels of IgG anticardiolipin antibody.

CONCLUSION: Heparin may act by directly binding APA in vivo, thereby decreasing the adverse effects of APA in women with APA associated RPL.