During pregnancy, labor and delivery

Your doctor might prescribe heparin, another blood-thinning medication, to prevent blood clots. This medication is usually given through a syringe inserted into the fat under the skin. Heparin has been shown in studies to be safe and effective during pregnancy.

However, you're still at risk of bleeding while taking heparin or other blood-thinning medications. If you notice indications of bleeding, contact your doctor.

Even when taking blood-thinning medications, you're at risk of developing blood clots during pregnancy. Watch for signs or symptoms of blood clots, such as chest pain or leg swelling. Contact your doctor immediately if you notice unusual signs or symptoms.

Blood-thinning medications are usually stopped during labor and delivery, unless you're at very high risk of blood clots.