It is a deep vein thrombosis of the lower extremities and pulmonary artery thromboembolism that occurs in women during pregnancy, and it is one of the important causative factors of death during pregnancy and perinatal period. Both congenital and acquired thromboembolism and its risk factors play an important role in miscarriage, fetal growth restriction in utero and pre-eclampsia. For the safety of the mother and fetus, effective prevention, early diagnosis and appropriate treatment of lower extremity deep vein thrombosis and pulmonary artery thromboembolism during pregnancy are warranted.
What is the incidence of thromboembolism in pregnancy?
Lower extremity deep vein thrombosis and pulmonary artery thromboembolism have been reported to account for 40% of pregnancy-related deaths. The risk of thrombosis in women during pregnancy is 5 times higher than in women of the same age. The incidence of venous thromboembolism is higher during pregnancy and delivery, and the incidence of pulmonary embolism and mortality are correspondingly higher in those with untreated deep vein thrombosis. The majority of DVTs occur before delivery, with half of them occurring before 15 weeks of gestation. The main sources of pulmonary embolism during pregnancy are DVT in the lower extremities and DVT in the pelvis.
What are the three basic factors in the formation of venous thromboembolism?
According to the theory proposed by Virchow in 1850, endothelial cell damage, hypercoagulable state of blood, and slow blood flow remain the three basic factors of venous thromboembolism.
Why is pregnancy, delivery and lactation prone to venous thromboembolism?
It is related to the following risk factors.
1. Compression of the veins by the enlarged uterus.
2. The effect of estrogen and progesterone decreases the tension of blood vessels and slows down the flow of venous blood.
3.Some pregnant women are bedridden for a long time, which affects the venous blood return.
4.The activity of fibrinogen and coagulation factors increases during pregnancy, and the coagulation inhibitory protein and fibrinolytic activity decreases.
5.Vascular endothelial cell damage during delivery.
6, Advanced maternal age and cesarean delivery.
7, smoking, obesity, ever taking birth control pills, taking high dose estrogen back after delivery, venous insufficiency of lower limbs, etc.
What is the clinical manifestation of venous thromboembolism during pregnancy?
Because venous thromboembolism presents with swelling of the lower extremities and dyspnea, it is sometimes easily confused with the physiological manifestations of pregnancy and results in missed diagnosis. It has been found that pregnant women without any symptoms or signs may have varying degrees of lower extremity deep vein thrombosis. Those with symptoms show swelling and pain in the affected limbs, and in case of pulmonary embolism, they can have respiratory distress. Even hypotension, shock, heart failure, coma and sudden death may occur.
How to prevent thromboembolism in pregnancy?
1.If the patient has family history of thrombosis, antithrombin III, protein C and protein S should be checked.
2.Prevent the hypercoagulable state of blood, especially for those who take contraceptive pills for a long time.
3.Advocate natural childbirth and minimize cesarean delivery.
4.Increase exercise, drink more water and eat more vegetables and fruits.
5.Check and deal with various risk factors.