DVT Prevention

DVT & Pregnancy

One small, but possible risk to your body during pregnancy – and for up to six weeks after birth – is that of a venous
thrombosis, or blood clot. On average, one to two women in every 1,000 will get a venous thrombosis during
pregnancy or just after delivery. Although only a few women are affected, having a thrombosis can affect your health, not
only during the pregnancy but also in later years. For example, problems such as varicose veins are more common after a
thrombosis, and the contraceptive pill should not be used if you have had a thrombosis. In addition it is also important to know
that the majority of these clots can be prevented.


Why are there greater risks of blood clots
during pregnancy?

Thrombosis can affect anyone, but being pregnant makes your blood more likely to clot. Doctors believe that the changes in clotting of the blood are designed to reduce bleeding at the time of normal delivery.  When you’re carrying a baby there is a dramatic reduction in the speed of blood flow in your veins, which carry the blood from your legs back to the heart. Doctors think that this is due to the effect of pregnancy hormones on the veins and also because of the womb getting bigger as the pregnancy advances. The reduction in blood flow becomes obvious in pregnancy by 16 weeks and is at its most sluggish closer to full-term as your body gets ready for the actual delivery. The blood flow does not return to normal until six weeks after delivery. This sluggish flow in the veins is why many women get some swelling of the legs when they are pregnant.  It is this reduction in blood flow, combined with the increased clotting tendency while pregnant that can result in a clot in the leg. This condition can be prevented, and if it does occur, can be treated.  Also, at the time of delivery, as the baby presses on the veins in the pelvis, minor damage can occur to these veins leading to an increased risk of having a clot for up to six weeks after delivery