Values and preferences towards the use of prophylactic low-molecular-weight heparin during pregnancy: A convergent mixed-methods secondary analysis of data from the Decision Analysis in SHared decision making for Thromboprophylaxis during Pregnancy (DASH-TOP) study

Abstract Background: Venous thromboembolism (VTE) in pregnancy is a major cause of maternal morbidity and mortality, and the use of preventive low-molecular-weight heparin (LMWH) can be challenging. Clinical guidelines recommend eliciting pregnant individuals’ preferences towards the use of daily injections of LMWH and discussing the best option through a shared decision-making (SDM) approach. Our aim was to identify individuals’ preferences concerning each of the main clinical outcomes, and categorize attributes influencing the use of LMWH during pregnancy. Methods: Design: Convergent mixed-methods. Participants: Pregnant women or those planning a pregnancy with VTE recurrence risk. Intervention: A SDM intervention about thromboprophylaxis with LMWH in pregnancy. Analysis: Quantitatively, we report preference scores assigned to each of the health states. Qualitatively, we categorized preference attributes using Burke’s pentad of motives framework: scene, agent, agency, act, and purpose. We use mixed-method convergent analysis to report findings using side-by-side comparison of concordance/discordance. Results: The least valued health state was to experience a pulmonary embolism (PE), followed by major obstetrical bleeding (MOB), deep vein thrombosis (DVT), and using daily injections of LMWH (valued as closest to a ‘healthy pregnancy’). Women's previous experiences, access to care (scene) and shared decision-making (agent) affected preferences. LMWH's benefits were noted, but substantial drawbacks described (agency). The main goal was avoiding the risk of VTE (purpose). Side-by-side comparisons revealed concordance between motives and DVT and PE health states. Discordance appeared between using daily injections of LMWH and agent- and agency motives and between MOB and the agency motive. Conclusions: Mixed-methods provide a nuanced understanding of women's LMWH preferences, by quantifying health states preferences and exploring attributes qualitatively. Incorporating both methods may improve patient-centered care around preference-sensitive decisions in thromboprophylaxis during pregnancy.