Therapeutic role of low molecular weight heparin and fat-soluble vitamins in pregnancy-associated prethrombotic conditions.

Pregnancy is a physiological hypercoagulable state associated with an increased risk of venous thromboembolism (VTE) and other prethrombotic conditions that contribute significantly to maternal and fetal morbidity and mortality. While low molecular weight heparin (LMWH) remains the cornerstone of prophylaxis and treatment due to its efficacy and safety profile, emerging evidence suggests that thrombosis in pregnancy is a multifactorial process involving endothelial dysfunction, inflammation, oxidative stress, and impaired placental development. These interconnected pathways highlight the limitations of anticoagulation alone in addressing the full spectrum of disease mechanisms. Fat-soluble vitamins, including vitamins D, K, E, and A, play critical roles in regulating vascular integrity, immune responses, oxidative balance, and coagulation pathways. Deficiencies or imbalances in these vitamins have been associated with adverse pregnancy outcomes such as preeclampsia, intrauterine growth restriction, recurrent pregnancy loss, and preterm birth. Mechanistically, these vitamins modulate upstream processes that contribute to thrombotic risk, complementing the downstream anticoagulant effects of LMWH. This review synthesizes current evidence on the pathophysiology of pregnancy-associated prethrombotic conditions, the therapeutic role of LMWH, and the biological functions of fat-soluble vitamins in maternal-fetal health. Furthermore, it proposes a synergistic model in which LMWH and fat-soluble vitamins act through complementary mechanisms to target both the causes and consequences of thrombosis. Clinical evidence supporting the independent roles of these interventions is discussed, and a conceptual model is presented. Despite a strong mechanistic rationale, clinical data evaluating combined LMWH and vitamin-based strategies remain limited. Future research should focus on randomized controlled trials, biomarker-guided approaches, and precision medicine strategies to optimize treatment. The integration of anticoagulant therapy with targeted nutritional modulation represents a promising avenue for improving pregnancy outcomes and advancing the management of thrombotic disorders in maternal-fetal medicine.