Can a pregnant patient have unilateral pitting edema in only one leg?

From the Guidelines

Yes, a pregnant patient can have unilateral pitting edema in only one leg, which requires prompt medical evaluation as it may indicate a deep vein thrombosis (DVT). While bilateral lower extremity swelling is common during pregnancy due to normal physiological changes like increased blood volume and pressure from the growing uterus on pelvic veins, unilateral swelling is not typical and should raise concern. According to the European Society of Cardiology guidelines 1, leg swelling is a frequent finding in pregnancy, and since DVT is left sided in 85% of cases, due to compression of the left iliac vein by the right iliac artery and the gravid uterus, specifically swelling of the left leg is suspicious.

DVT risk is higher during pregnancy due to hypercoagulability, venous stasis, and vascular damage, as noted in the guidelines on diagnosis and management of acute pulmonary embolism 1. If a pregnant patient presents with one-sided leg swelling, especially if accompanied by pain, warmth, or redness, they should seek immediate medical attention. Diagnosis typically involves ultrasound examination, and if DVT is confirmed, treatment usually consists of therapeutic anticoagulation with low molecular weight heparin throughout pregnancy, as it doesn't cross the placenta. Other less common causes of unilateral edema during pregnancy include cellulitis, lymphedema, or external compression of veins by the gravid uterus in certain positions.

Some key points to consider in the evaluation and management of unilateral pitting edema in pregnancy include:

• The clinical presentation and risk factors for DVT, such as left leg swelling and calf circumference difference 1
• The use of diagnostic tests like ultrasound and D-dimer measurement, taking into account the physiological changes during pregnancy 1
• The importance of prompt treatment with therapeutic anticoagulation if DVT is confirmed, to reduce the risk of complications and improve outcomes.

From the Research

Unilateral Pitting Edema in Pregnancy

• Unilateral pitting edema in pregnancy can occur, although it is less common than bilateral edema 2.
• A study published in the Journal of the Indian Medical Association reported a case of unilateral lower limb edema in a pregnant woman, which was diagnosed as deep venous thrombosis 3.
• The patient in this case presented with severe pain and swelling of the left lower limb, and Doppler ultrasound showed a thrombus in the left femoral vein.
• Another study published in Therapeutische Umschau noted that atypical edema localization and local, unilateral edema should raise suspicion of other dangerous complications of pregnancy, such as deep vein thrombosis 2.
• The use of diuretics is generally not recommended for treating edema in pregnancy, except in cases of pulmonary edema associated with preeclampsia 2.

Causes and Risk Factors

• Pregnancy is a known risk factor for pitting edema of the lower limbs, which can occur due to fluid overload and chronic venous insufficiency 4.
• The blockage of lymphatic channels by the gravid uterus can also contribute to lymphorrhea and edema in pregnancy 4.
• Other risk factors for edema in pregnancy include hypertension, obesity, and smoking 4.

Treatment and Management

• The treatment of unilateral pitting edema in pregnancy depends on the underlying cause, and may involve the use of compression stockings, elevation of the affected limb, and other supportive measures 5.
• In cases of deep vein thrombosis, anticoagulation therapy with heparin may be necessary 3.
• Reflexology and water immersion have also been shown to be effective in reducing symptoms of edema in pregnancy, although more research is needed to confirm these findings 5.