The STOP CLOT Pilot Study: Study of Low Molecular Weight Heparin in High Risk Cesarean Section

Venous thromboembolism (VTE) remains the most common cause of maternal death in the developed world. VTE includes two conditions, deep vein thrombosis (DVT) and pulmonary embolism (PE). DVT refers to a blood clot that has formed in a deep vein, often in the legs and/or pelvis and PE refers to the passage of these clots into the lungs (which can be fatal). VTE is up to 10 times more common in pregnant women than non-pregnant women of comparable age. More than a third of pregnancy related VTE occur during the 6 weeks after delivery. When compared with vaginal delivery, cesarean delivery further increases the risk of pregnancy associated VTE by three-fold. A medication called low molecular weight heparin is sometimes prescribed during pregnancy and after delivery to prevent VTE. However, clinical practice varies because there hasn't been adequate research to determine that this medication is safe and effective at preventing VTE during this time. The potential benefits of the medication must also be weighed against its cost and possible side effects. The researchers are conducting a study that will assess the effectiveness and safety of low molecular weight heparin in women who are at moderate to high risk of VTE after a cesarean section. They will monitor these women to determine if those who received the medication have fewer blood clots. Participants will also be monitored closely for any side effects.