Which anticoagulant is closer to delivery because of its shorter half-life?

• A. Low molecular weight heparin
• B. Warfarin
• C. Unfractionated heparin
• D. Aspirin

Answer: (C)

Near delivery, you want an anticoagulant that can be stopped quickly and whose effects dissipate fast, so bleeding risks during labor or cesarean can be managed and reversal can be prompt if needed. Unfractionated heparin fits this need because its anticoagulant effect wanes within about 1–2 hours after stopping the infusion, and it can be rapidly reversed with protamine sulfate. This makes it the most controllable option when delivery is imminent.

Low molecular weight heparin has a longer and less predictable half-life and is not as readily reversible, which makes it less ideal right before delivery. Warfarin has a long half-life and takes days to reverse, so it’s unsuitable in the peripartum period. Aspirin is primarily an antiplatelet agent, not an anticoagulant used for these situations, and its effects are not easily reversed quickly either.