Thrombosis and pregnancy

Women are exposed to an increased risk of thrombosis during pregnancy. With appropriate thrombosis prophylaxis during pregnancy, the risk of blood clots can be reduced. Discover the risk factors for thrombosis and learn more about the development and treatment of a blood clot.

Thrombosis and pregnancy

A quick overview:

Causes and origin: Thrombosis during pregnancy

The risk of developing deep pelvic or leg vein thrombosis is increased during pregnancy and childbirth. Why is that?

This is mainly due to the following two causes:

  • Hormonal balance: The hormonal changes triggered during pregnancy cause the vein walls to become more elastic and dilate. The blood’s composition also changes: This already has an effect on blood clotting from the beginning of pregnancy.
  • Pressure on the abdominal and pelvic veins: As the child grows and moves downwards into the pelvis during the last trimester of pregnancy, there may be a mechanical obstruction to the flow of blood in the abdominal and pelvic veins.

Both factors slow down the flow of blood and thus promote the formation of a blood clot (thrombus) in the veins.

The following additional risk factors can also aggravate thrombosis:


  • An advanced age (over 35 years) 1
  • Severe obesity
  • Existing varicose veins (varicosis)
  • Previous vein complaints
  • A known vein disease in the family
  • Smoking
  • Caesarean section
  • Diabetes mellitus
  • High blood pressure

Towards the end of pregnancy, a pregnant woman’s mobility is often restricted by an expanding tummy. Although rest breaks are important, regular exercise should be undertaken to support venous blood flow and reduce the risk of thrombosis. Moderate movements are suitable, for example, taking a walk in the fresh air or swimming.

The risk of thrombosis is still elevated in the period after birth.

Things to know:

All important information on thrombosis in general, symptoms and treatment

Thrombosis: Diagnosis & Therapy

Detecting thrombosis in pregnancy

Thromboses usually occur on one side. Symptoms can be mild and sometimes the person does not feel anything at first. This can lead to thrombosis not being detected in the initially stages. The symptoms can sometimes appear suddenly and intensely. How does a thrombosis manifest itself? Typical symptoms include: 2

  • A feeling of tension in the affected leg
  • Swelling of the affected leg
  • A pressing pain on the inside of the foot
  • A red-blue discolouration in the affected area
  • Calf pain when flexing the foot or applying pressure

Should you experience any of the above symptoms, contact your doctor immediately. The early diagnosis of “thrombosis in pregnancy” is essential, in order that the treating physician can immediately initiate the appropriate treatment.

The professional opinion counts

During pregnancy, a regular medical examination of the expectant mother and her child is particularly important. If the doctor makes a diagnosis during pregnancy, he or she will arrange for the necessary therapy. In the event of vein or back issues, the doctor can prescribe suitable medical aids from medi as needed. You can obtain these from trained specialist staff in specialist medical stores.

What complications can occur?

One serious complication of venous thrombosis is pulmonary embolism. Some or all of the clot is released, after which it travels through the bloodstream via the heart and to the lungs. If the blood vessels in the lungs become blocked, this can lead to cardiovascular arrest.

Pulmonary embolism as a possible consequence and complication of deep vein thrombosis represents a serious emergency situation. A doctor must be consulted immediately if symptoms – such as a shortness of breath or stabbing pains in the chest – occur.

Prevention and treatment of thrombosis during pregnancy

To keep the risk of thrombosis low, women should also make sure they get enough exercise and drink plenty of fluids during pregnancy.

If a venous thrombosis nevertheless occurs, treatment must start as soon as possible. To dissolve a blood clot, the doctor immediately initiates a medicinal therapy involving blood-thinning agents. In order to relieve symptoms such as swelling, pain and the sense of heaviness in the legs, as well as to prevent further complications, compression therapy – usually with medical compression stockings – is also recommended.

Compression promotes the efficiency of the muscle pump function in the legs and, with it, the venous return flow.

To prevent this from happening in the first place, thrombosis prophylaxis is recommended during pregnancy:3

  • Medical compression stockings 
  • Regular, moderate exercise
  • Adequate fluid intake

Medical compression stockings from medi are suitable for therapy and are available in a variety of colours and designs. If necessary, they can be prescribed by a doctor. Their high level of user comfort, therapeutic benefits and aesthetics make them hugely popular with wearers. Of course, there are compression tights for pregnant women with an elastic, high waistband (panty top) for a comfortable feeling of wellbeing.

Product overview

Clinical studies confirm: Medical compression stockings relieve typical complaints during pregnancy


  • An improvement in the veins’ pumping function4,5
  • A significant reduction in complaints such as pain, swelling and a sense of heaviness in the legs6
  • A positive effect on orthostatic complaints7
  • Significant relief from nausea, vomiting and dizziness8

Show sources

Bundesärztekammer (Arbeitsgemeinschaft der deutschen Ärztekammern) und Kassenärztliche Bundesvereinigung: Schwangerschaft: Thromboserisiko nach Hospitalisierung erhöht. URL: (03.09.2020).

Internisten im Netz: Venenthrombose: Erste Anzeichen & Symptome. URL: (03.09.2020).

Encke A et al: S3-Leitlinie Prophylaxe der venösen Thromboembolie (VTE). URL: (04.09.2020).

Rabe E et al. S2k-Leitlinie: Medizinische Kompressionstherapie der Extremitäten mit Medizinischem Kompressionsstrumpf (MKS); Phlebologischem Kompressionsverband (PKV) und Medizinischen Adaptiven Kompressionssystemen (MAK). Stand 12/2018.Online veröffentlich unter: (Letzter Zugriff: 20.07.2020).

Büchtemann AS et al. The effect of compression therapy on venous haemodynamics in pregnant women. Br J Obstet Gynaecol 1999;106(6):563–569.

6 Saliba Júnior OA et al. Graduated compression stockings effects on chronic venous disease signs and symptoms during pregnancy. Phlebology 2020;35(1):46–55.

7 Austrell C et al. Maternal and Fetal Haemodynamics during late pregnancy: Compression hosiery treatment. Phlebology 1993;8:155֪–157.

8 Mendoza E, Amsler F. A randomized crossover trial on the effect of compression stockings on nausea and vomiting in early pregnancy. Int J Womens Health 2017;9:89-99.