What is the cause of pitting edema in pregnancy?

From the Guidelines

Pitting edema in pregnancy is most commonly caused by normal physiological changes, including increased blood volume and pressure on veins from the growing uterus, rather than a pathological condition like pre-eclampsia or gestational hypertension, as oedema occurs in up to 60% of normal pregnancies and is no longer used in the diagnosis of pre-eclampsia 1.

Normal Physiological Changes

Pitting edema during pregnancy is often a result of the body's natural adaptations to support the growing fetus. This includes increased blood volume, which can lead to fluid accumulation in the tissues, particularly in the feet, ankles, and legs. The pressure exerted by the expanding uterus on the veins can also contribute to edema by impairing blood flow back to the heart.

Management of Edema

To manage pitting edema during pregnancy, several strategies can be employed:

• Elevate your legs whenever possible, especially when sitting or lying down, to reduce swelling.
• Wear comfortable, supportive shoes and avoid tight clothing that can restrict circulation.
• Engage in regular, gentle exercise like walking or swimming to improve circulation and reduce fluid retention.
• Stay well-hydrated by drinking plenty of water, as this can help reduce fluid retention.
• Reduce sodium intake in your diet, as excessive salt consumption can worsen edema.
• Rest frequently throughout the day with your feet elevated above heart level.
• Consider using compression stockings to prevent fluid accumulation in the lower extremities.

When to Seek Medical Attention

While mild edema is a common and normal part of pregnancy, sudden or severe swelling, especially in the face or hands, could be indicative of a more serious condition like preeclampsia and requires immediate medical attention 1. It's essential to monitor edema and report any concerns to a healthcare provider to ensure the health and well-being of both the mother and the fetus.

From the Research

Causes of Pitting Edema in Pregnancy

• Pitting edema in pregnancy can be caused by fluid overload and chronic venous insufficiency 2
• Pregnancy is a known risk factor for pitting edema, and the blockage of lymphatic channels by the gravid uterus may contribute to lymphorrhea 2
• Other factors that may contribute to pitting edema in pregnancy include:
  • Hypertension 2
  • Obesity 2
  • Vaping 2
  • Previous history of venous conditions, such as vascular insufficiency and thrombosis 3
  • Lack of physical exercise during pregnancy 3
• Pitting edema can also be a sign of pre-eclampsia, especially when associated with raised blood pressure or proteinuria 4

Related Conditions

• Varicose veins and leg oedema are common symptoms in pregnancy, and can cause pain, feelings of heaviness, night cramps, and paraesthesiae 4, 5
• Deep vein thrombosis (DVT) is a rare but serious complication of pregnancy, and can be caused by risk factors such as prolonged bed rest, pelvic or leg trauma, and obesity 6
• Lymphorrhea, or weeping edema, is a rare condition that can occur in pregnancy, and may be caused by the blockage of lymphatic channels by the gravid uterus 2

Treatment and Management

• Compression therapy, such as wearing circular-knit compression garments, can be an effective means of preventing and treating venous thrombosis and lower limb edema in pregnant women 3
• Physical exercise during pregnancy can also help to reduce the risk of lower limb edema 3
• Loop diuretics, such as torsemide, may be used to treat profound pregnancy-associated edema, but further study is needed to assess their safe use in pregnant women 2