How Does Pregnancy Affect Vein Health?

When you’re expecting, your body undergoes various physiological changes to support healthy fetal growth and development. Unfortunately, many of these pregnancy-related changes can pose a challenge for certain aspects of maternal health. 

In this month’s blog, our team at Vascular Vein Centers explains how pregnancy can affect vein health. It offers helpful strategies to reduce your risk of developing vein problems through the prenatal and postpartum periods.  

Understanding how pregnancy affects your veins 

Pregnancy is sometimes referred to as “nature’s stress test” because of the increased demand it places on your circulatory system. As your pregnancy hormones surge and your blood volume swells, your heart works harder — and so do your veins. 

During pregnancy, three major factors affect vein health and function, particularly in the lower extremity vessels that work against gravity to keep blood flowing from your legs back to your heart. The first two factors also remain after delivery, gradually improving over the postpartum period.  

Increased workload

To support the needs of your developing fetus in addition to those of your body, pregnancy increases your blood volume. As your plasma and red blood cell mass increase, you could experience a total blood volume increase between 20% and 100% over pre-pregnancy levels; a 45% increase is typical. 

Compared to arteries, veins are low-pressure, low-velocity vessels that expand easily. This is because veins act as your body’s primary “blood reservoir,” holding about 70% of your blood supply at any given time. Even so, pregnancy taxes venous capacity, making veins work harder to accommodate the significantly larger blood volume.   

Reduced functionality

At the same time, a surge of pregnancy hormones (progesterone and relaxin) causes the walls of your blood vessels to relax and stretch. This is why arterial blood pressure is often lower in the first two trimesters, despite increased blood volume. 

In your veins, vascular relaxation can have another effect: sluggish blood flow. 

Unlike your arteries, which rely on your heart to pump blood through them effectively, your veins rely on skeletal muscle contraction and internal valves to keep blood flowing. As veins become more relaxed in pregnancy, their valves weaken, and your circulation slows.

Pressure on the IVC

As your largest vein, the inferior vena cava (IVC) is the “receiving superhighway” for all the veins in your lower body. This major vein starts in your lower pelvic area — just behind your uterus — and runs all the way to your heart. 

Toward the end of the second trimester, your expanding uterus starts putting pressure on the IVC. As uterine size and weight increase rapidly in the third trimester, the resulting IVC strain can inhibit normal blood flow from your lower extremities. 

Common prenatal and postpartum vein problems 

These three influences over lower extremity vein health make certain vein problems more common during pregnancy. In fact, these conditions are so common among expectant mothers that pregnancy is considered a risk factor for them. 

When you’re pregnant, especially in the later trimesters, you’re more likely to develop leg swelling (lower extremity edema). You’re also more vulnerable to:

• Spider veins 
• Varicose veins  
• Hemorrhoids 
• Vulvar varicosities

Each of these issues occurs in the same basic way: weakened vein valves, overstretched vein walls, and high blood volume lead to sluggish circulation and blood pooling, causing venous pressure that swells and distorts the affected vein area. 

Spider veins are small, distorted vessels at the ends of veins (capillaries, venules), while varicose veins are larger, distorted surface veins. Hemorrhoids are varicose veins in or around the rectum, and vulvar varicosities are varicose veins on the outer genital area. 

Pregnancy and DVT  

During pregnancy and through the postpartum period (the first three months after delivery), you’re also at higher risk of developing deep vein thrombosis (DVT), or a blood clot in one of your subsurface leg veins. 

This serious, potentially life-threatening risk comes from slower venous circulation coupled with pregnancy-related changes that make blood “stickier” and more likely to clot as a way to prevent massive blood loss during delivery.   

Vein support during pregnancy and after delivery

Luckily, mild pregnancy-related vein issues typically resolve within a few weeks of childbirth. You can also take steps to reduce your chances of developing more severe vein problems by supporting venous health and lower extremity circulation. This means:

• Promoting leg circulation through daily exercise 
• Sleeping on your left side to reduce IVC pressure
• Elevating your legs whenever you’re sitting down 
• Avoiding sitting or standing still for long periods

If you have other significant risk factors for venous disease (e.g., family history, excess weight), wearing maternity hose or compression socks can also be helpful.  

Post-pregnancy vein treatment in Central Florida

If you do develop varicose veins or another vein problem during pregnancy, schedule an evaluation at Vascular Vein Centers. As the only IAC-accredited vein testing experts in Central Florida, our post-pregnancy vein care specialists can assess your vein changes and provide individualized treatment options. 

To learn more, contact our team at Vascular Vein Centers by calling 877-244-8558 today. We have six Central Florida offices in College Park of Orlando, Kissimmee, Lake Mary, Waterford Lakes of East Orlando, Davenport/Haines City, and The Villages, Florida.