Thromboembolic events in pregnancy: diagnosis and prevention
The definition of venous thromboembolism (VTE) includes two pathological conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE) . DVT is the partial or complete obstruction of a vein of the deep venous circulation of a limb (most frequently the legs) by a blood clot, called a thrombus .
PE is the acute, partial or complete obstruction of one or more branches of the pulmonary arterial circulation by thrombotic material from the deep venous circulation. In 95% of cases, PE originates from a DVT of the lower limbs.
The incidence of VTE in pregnancy is about 5 times higher than in non-pregnant women, while in the puerperium period the risk increases up to 20 times.
Causes of increased incidence of VTE in pregnancy
The causes of the increased probability of this pathology are the following:
- physiological hypercoagulable state of pregnancy (increased levels of certain procoagulant factors and decreased levels of anticoagulant proteins);
- increased stasis of the venous circulation;
- vascular damage in connection with childbirth.
Symptoms
Symptoms of a DVT of the lower extremities include swelling, usually unilateral, associated with a sense of tension, pain, redness and sometimes difficulty walking.
Suspicion of a PE arises when tachycardia, difficulty breathing and chest pain also appear. However, some symptoms can be confusing, especially during pregnancy.
The diagnosis
A clinical suspicion of DVT can be confirmed by performing a venous EcocolorDoppler , a quick, inexpensive test that does not involve risks during pregnancy.
To ascertain a possible PE, it is normally necessary to perform a pulmonary AngioTac , or a lung Scintigraphy (these tests, during pregnancy, will be prescribed with caution and only if really necessary, in order to minimize the risk of PE). radiation exposure).
A test, called a d-dimer , is also usually done on a blood draw; the d-dimer value increases in the presence of thromboembolic events, but in pregnancy it tends to be elevated even in normal conditions.
Prevention
There are some “mechanical prophylaxis” strategies that help prevent thrombotic events in the lower limbs.
These include physical activity , both active and passive, with early recovery of ambulation after delivery, if not contraindicated. Alongside physical activity, the use of graduated compression stockings can be very important , which have the purpose of facilitating the return of venous circulation.
This precaution prevents the aggravation of varicose veins, reducing symptoms such as a sense of heaviness, swelling and pain. In some selected cases, a pharmacological “thromboprophylaxis” may be suggested, usually with low molecular weight heparin .
The use of an antithrombotic prophylaxis always involves even a small risk of bleeding, it should therefore be undertaken, on clinical judgment, when the thrombotic risk is consistent (eg in the case of previous thrombotic events or relevant thrombophilic defects).
Therapies
The treatment of thromboembolic episodes in pregnancy involves the use of heparin (low molecular weight or unfractionated) in therapeutic doses.
Low molecular weight heparin is usually preferred because it is easier to administer and manage, but both drugs are considered safe in pregnancy.
Oral anticoagulant therapy, which involves the use of warfarin , is usually avoided in pregnancy as it involves an increased risk of miscarriage and fetal malformations; it can be used with greater safety only after delivery.
Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.
Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.