Successful use of heparinoids in a pregnancy complicated by allergy to heparin

An analysis of clinical outcomes of 91 pregnancies in 83 women treated with danaparoid (Orgaran)

Danaparoid case reports of 91 pregnancies in 83 patients with a history of thrombophilia and/or intra-uterine growth retardation have been analysed. All had intolerance to the heparins including HIT and acute or past thromboses or a history of repeated pregnancy loss (RPL). Danaparoid was started in the first, second and third trimesters in 60.2%, 19.3% and 20.5% pregnancies respectively at a dosing intensity of 1000 to 7500 U/day. Subcutaneous and/or intravenous administration was continued for a median 105 days (range 1-252) during pregnancy and 7 days (range 2 to 56) post-partum. The live birth rate was 90.4% (75/81) and danaparoid was restarted after 37 deliveries. Maternal adverse events in 46.2% of the pregnancies included 2 post cesarean deaths (a failed post-operative resuscitation and a major bleed in a patient refusing transfusion), 3 non-fatal major bleeds (associated with cesarean section and faulty placental implantation), 3 thrombo-embolic events unresponsive to danaparoid dose increase and 10 recurrent rashes. Seven early miscarriages, 1 therapeutic termination and 1 neonatal death occurred. In 13 reports a maternal, but no fetal, adverse event was attributed to danaparoid. Anti-Xa activity levels in maternal plasma were between 0.1 and 1.2 U/mL, absent from 6 fetal cord blood samples and 0 - 0.07 U/mL in the 5 maternal breast milk samples tested.

CONCLUSION

The successful birth rate and adverse event profile indicates that danaparoid can be an effective and safe alternative anti-thrombotic in pregnancies complicated by HIT or intolerance or resistance to (LMW)heparins.

Treatment and prophylaxis of venous thromboembolism during pregnancy

The treatment and prevention of deep vein thrombosis (DVT) and pulmonary embolism (PE) in pregnant patients is challenging for several reasons. Coumarins can cause embryopathy and other adverse effects in the fetus. Although unfractionated heparin and low-molecular-weight heparins, the cornerstones of initial therapy, are safe for the fetus, they can have significant maternal side effects, including osteoporosis and thrombocytopenia. Because they must be given parenterally, long-term administration is inconvenient. Further, although low-molecular-weight heparins probably cause less maternal osteoporosis and thrombocytopenia than unfractionated heparin, the appropriate dosing regimens for prevention and treatment of thrombosis during pregnancy have not been established. In addition, there is a paucity of reliable information on the incidence of venous thromboembolism and the risk of recurrent thrombosis during pregnancy. This paper briefly reviews the areas of controversy and provides recommendations for the treatment and prophylaxis of acute deep vein thrombosis and pulmonary embolism in pregnant patients.