Grant: Project Grant

Women are at an increased risk of developing blood clots (venous thrombosis, including deep vein thrombosis or pulmonary embolism) during pregnancy and in the postpartum period. For postpartum women who have additional risk factors for venous thrombosis, it is still unknown whether preventative blood thinners are needed after delivery. Previous studies have evaluated whether daily low-molecular-weight heparin injections after delivery prevents blood clots, however, one major barrier to study recruitment has been patients' lack of comfort with doing the injections at home. Recently, low-dose aspirin has been shown to be effective at preventing blood clots after orthopedic surgery. Low doses of aspirin is considered safe while breastfeeding. We plan to conduct a study where postpartum women at risk of blood clots are randomized to 6 weeks of low-dose aspirin versus placebo. The main purpose of this pilot study is to see if we can recruit enough women to make a larger trial feasible. Over a 6 week time period we will complete a D-dimer blood test and leg ultrasounds to screen for deep vein thrombosis, as well as track symptoms of blood clots, bleeding and side effects of aspirin. We will also call subjects at 90 days to see if there are any symptoms of blood clots, bleeding or side effects. If this pilot study is feasible, then the clinical information we collect will be used in the larger trial to determine if aspirin prevents more blood clots in postpartum women compared to placebo. By competing this pilot study we will be able to better prepare for a larger trial to definitively answer the question of whether women at risk of blood clots may benefit from taking aspirin after delivery to prevent blood clots.