Swelling during pregnancy is extremely common, affecting roughly 70% of women at some point during their pregnancy, most often in the third trimester. It happens because your body retains significantly more water and sodium than usual, your blood volume increases substantially, and your growing uterus puts pressure on the large vein that carries blood back from your lower body. The good news: most pregnancy swelling is harmless, and several straightforward strategies can bring real relief.
Why Pregnancy Causes Swelling
Your body undergoes major fluid changes during pregnancy. Plasma volume expands through sodium and water retention, increasing the total amount of fluid circulating in your system. Gestational weight gain averages around 11 kg (about 24 pounds), and a large portion of that is water. At the same time, your blood vessels relax and widen, which lowers blood pressure but also allows more fluid to seep from your bloodstream into surrounding tissues.
As your uterus grows, it presses on the inferior vena cava, the large vein responsible for returning blood from your legs and pelvis back to your heart. This pressure slows blood flow from your lower body, causing fluid to pool in your feet, ankles, and calves. Gravity makes it worse throughout the day, which is why many women notice their shoes feel tight by evening but fit fine in the morning.
Sleep on Your Left Side
One of the simplest things you can do is sleep on your left side. This position takes pressure off the inferior vena cava, allowing blood to flow more freely from your legs back to your heart. The Mayo Clinic recommends elevating your legs slightly with pillows while you sleep, which further helps fluid drain away from your lower extremities overnight. Many women notice a meaningful difference in morning ankle size after making this switch.
Get Into the Water
Swimming or simply standing in a pool is one of the most effective remedies for pregnancy swelling, and it works through a mechanism you might not expect. The hydrostatic pressure of water physically pushes fluid from your tissues back into your bloodstream. This effect is proportional to how deep you’re submerged, and research shows it’s even more pronounced in women who already have significant edema. The fluid shift triggers your kidneys to produce more urine, flushing out the excess. Even 20 to 30 minutes of standing or gentle movement in chest-deep water can produce noticeable relief.
Stay Well Hydrated
It sounds counterintuitive, but drinking more water helps your body release retained fluid. When you’re dehydrated, your body holds onto sodium and water more aggressively. A study of pregnant women in their second trimester found that those with higher fluid intake had significantly better hydration markers, with dehydration rates dropping from nearly 27% in the lowest intake group to 0% in the highest. Adequate hydration supports kidney function, helps regulate your metabolism and temperature, and signals your body that it doesn’t need to hoard extra fluid. Aim for water as your primary drink rather than sugary or caffeinated beverages.
Elevate Your Feet and Keep Moving
Whenever you’re sitting, prop your feet up. Even a footstool under your desk makes a difference by working with gravity to move fluid away from your ankles. Avoid sitting or standing in one position for long stretches. If your job keeps you at a desk, take short walking breaks every hour or so. Walking activates your calf muscles, which act as a pump to push blood upward through your veins.
Gentle exercise like walking, prenatal yoga, or stationary cycling keeps your circulation active throughout the day. You don’t need intense workouts. Consistent, low-impact movement is what matters for fluid circulation.
Try Compression Stockings
Graduated compression stockings apply the most pressure at your ankle and gradually decrease toward your calf, helping push fluid upward. Research on pregnant women in late pregnancy used below-knee stockings with 27 mmHg of pressure at the ankle and 18 mmHg at the calf, which falls into the moderate compression range. You can find maternity compression stockings at most pharmacies. Put them on first thing in the morning before swelling builds up during the day for the best results.
Eat Potassium-Rich Foods
Potassium helps your body balance sodium levels, and since excess sodium drives fluid retention, getting enough potassium can help manage swelling. Foods naturally high in potassium, like bananas, sweet potatoes, spinach, avocados, and beans, are also naturally low in sodium, making them a good swap for salty snacks. Potassium also plays a role in keeping blood pressure in a healthy range during pregnancy, which benefits both you and your baby.
As for salt restriction specifically, the evidence is mixed. While dietary patterns heavy in fat, sugar, and salt are associated with higher pregnancy complication risk, a Cochrane review of randomized trials found that simply lowering salt intake did not prevent preeclampsia. You don’t need to eliminate salt entirely, but avoiding heavily processed and very salty foods is reasonable.
What Swelling Is Not Normal
Most pregnancy swelling is a nuisance, not a danger. But certain patterns of swelling can signal preeclampsia, a serious blood pressure condition. Normal swelling tends to be gradual and concentrated in your ankles and feet. Concerning swelling looks different: sudden puffiness in your hands, arms, or face, especially if it comes with rapid, unexpected weight gain from fluid retention. A woman with mild preeclampsia may not notice symptoms at all, which is one reason prenatal blood pressure checks matter so much.
Other warning signs that accompany problematic swelling include persistent headaches, vision changes (blurriness or seeing spots), and upper abdominal pain. If your swelling appears suddenly, involves your face or hands more than your feet, or comes alongside any of these symptoms, contact your provider promptly.
How Quickly Swelling Resolves After Delivery
After giving birth, your body still has a significant amount of extra fluid to clear. Some women actually experience worse swelling in the first few days postpartum, especially if they received IV fluids during labor. According to Cleveland Clinic, postpartum swelling typically resolves within about a week as your kidneys flush the excess fluid. You may notice increased urination and heavier sweating during this period, both of which are your body’s way of rebalancing. Staying hydrated and continuing to elevate your legs can help speed this process along.