Treatment of Recurrent Miscarriage of Thrombophilias and Clotting Disorders
Although conclusive data on its efficacy remains controversial, anti-thrombotic treatment with the blood thinner heparin. A low molecular weight form of heparin, enoxaprin (Lovenox), is also available. These agents are especially important in the setting of combined thrombophilias and in women with a history of prior thrombosis. It is believed that heparin may help to reduce the possibility of clot formation in the placental vessels, and therefore decrease the chance of miscarriage. A typical regimen would consist of heparin administered as a subcutaneous injection of 5000 units twice daily. Lovenox, at a dose of 40 mg subcutaneously once daily has also been show to be effective, and allows for a once daily dosing. One study with Lovenox demonstrated a 75% live birth rate in women with thrombophilias vs. 20% in untreated women.
The use of low-dose baby aspirin (80mg) for the prevention of recurrent pregnancy loss in women has been extensively studied. The mechanism for aspirin’s effectiveness is believed to be an improvement in microcirculation due to aspirin’s effect on prostaglandins, chemical substances that have numerous effects throughout the human body. It is felt that aspirin improves circulation by facilitating a prostaglandin profile that encourages improved placental blood flow through vessel dilation and inhibition of platelet aggregation (clumping) and adhesion (stickiness). Most studies of thrombophilias have incorporated aspirin with an anti-thrombotic such as heparin or Lovenox, with improved live births shown with this combination. In two prospective studies in women with recurrent miscarriages and the Antiphospholipid Syndrome, an antibody-associated acquired thrombophilias, live birth rates were 70-80% for the combination vs. 40% with aspirin alone. While large controlled studies with the genetic thrombophilias have not been performed, several studies have shown a similar live birth rate when aspirin is used in combination with an anti-thrombotic such as heparin or Lovenox.
Additional Therapy for Recurrent Miscarriage Clotting Disorders
Since folic acid intake may also lower homocysteine levels, a minimum of 1mg of folic acid should be part of the regimen in women with positive MTHFR. Some authorities suggest even higher doses of folic acid, up to 4 mg, although limited data is available on the efficacy of this dosing in the prevention of miscarriages. Additionally, B-12 and B-6 supplementation, both co-factors in folic acid metabolism, should be offered as well, with some authorities recommending up to 1000 mcg of Vitamin B-12 and 200 mg of Vitamin B-6. Folic acid at a dose of 1 mg is contained in most prenatal vitamins, and has been shown to be effective in the prevention of neural tube defects such as spina bifida. As such, folic acid intake should be considered part of good nutritional intake for a healthy pregnancy in all women.