Clotting Disorder / Thrombophilia

By RRM Academy Reviewed by Dr. Naomi Whittaker, MD, Board-Certified OBGYN, MIGS, NFPMC, FCI Updated May 7, 2026

A heritable or acquired tendency toward excessive blood clotting that can impair placentation and contribute to pregnancy loss. Inherited thrombophilias include Factor V Leiden mutation, prothrombin G20210A mutation, and protein C, protein S, or antithrombin deficiency. Acquired thrombophilia includes antiphospholipid syndrome (APS), which involves antibodies that interfere with phospholipid-binding proteins critical to normal coagulation and placental function.

The mechanism of pregnancy loss is primarily vascular. Microthrombi in the early placental vasculature impair the implantation bed and restrict blood flow to the developing embryo. Not all inherited thrombophilias carry the same risk level. Factor V Leiden heterozygosity confers modest increased risk; homozygous mutations and combined thrombophilias carry substantially higher risk.

RRM evaluation for thrombophilic conditions is part of the standard RPL workup and is also considered in women with a history of placental abruption, late fetal loss, or unexplained preterm birth. Treatment, when indicated, typically involves low-molecular-weight heparin during pregnancy, sometimes combined with low-dose aspirin. See Autoimmune/Thrombophilic Disorders for the full RPL context and evaluation protocols.⁷⁵

This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.