How Your Body Changes During Pregnancy

Your body’s blood volume increases up to 50% throughout your pregnancy. This means your heart has to work harder to pump more blood throughout your body, which causes your heart rate to increase by approximately 10-20 beats per minute. This can also lead to sinus pressure and congestion, swelling and edema, bleeding gums, and nosebleeds due to expanding blood vessels. After birth, your blood volume and heart rate will return to pre-pregnancy volume around 2 weeks after delivery.

The nausea of morning sickness , heartburn , constipation, diarrhea, and excess gas are all common during pregnancy, triggered by hormone changes that slow down digestion. As the uterus and baby grow, the pressure they can put on the digestive tract can also cause discomfort and digestive issues.

Fluctuating hormones and complex physical changes can tax your brain, which can lead to forgetfulness, difficulty recalling words, and trouble finding things. This is commonly called “pregnancy brain.” Research shows that the brain actually changes during pregnancy in the areas that control social cognition, perhaps to make adjustments for maternal attachment.

Skin changes are common during pregnancy and are often a result of shifting hormone levels. These changes can include acne, melasma (dark patches on the skin), stretch marks, and more sensitive skin. Most skin changes usually resolve in the postpartum period.

Stretch marks are a common skin change that affects up to 90% of pregnancies. They appear as streaky lines across your belly, breasts, butt, and thighs. Stretch marks are caused by the rapid stretching of your skin as your fetus grows and, contrary to what the market will try to sell you, research shows that they cannot be prevented with products (although oils and balms can help soothe your skin). They are typically most noticeable during the third trimester and can fade over time.

Melasma, often called ‘the mask of pregnancy,’ is a type of hyperpigmentation that causes dark patches to appear on your face. Melasma is caused by a rise in estrogen and progesterone, which cause an increase in melanin production. It occurs in up to 20% of pregnancies and often appears on the cheeks, nose, and sides of the face. Melasma typically fades naturally after giving birth and disappears (with treatment) within a year. Sun exposure can also make melasma darker and take longer to fade, so using adequate sun protection is important.

Acne is a common skin condition that can occur anytime, but it's especially common during pregnancy. Various factors can cause acne, but when it develops or worsens during pregnancy, it is most likely the result of fluctuating hormone levels. Pregnancy acne typically goes away postpartum.

Linea nigra appears as a dark vertical line down the center of your abdomen during pregnancy. It is caused by the darkening of the linea alba, a thin fibrous tissue that runs down the abdomen. Not everyone will experience this, but if you do, it usually develops during the second trimester and may get darker as you get closer to your due date. This typically recedes post-pregnancy and returns to its pre-pregnancy state.

Read here for a deep dive into skin changes during pregnancy and what you can do about them.

Rhinitis, or a constant stuffy nose, is common during pregnancy. It’s estimated that 20-32% of all people will experience nasal congestion at some point during their pregnancy. The exact cause of pregnancy rhinitis is unknown, but the leading theory is that hormonal changes during pregnancy (including an increase in placental growth hormone, which stimulates the growth of the fetus) cause swelling of nasal mucous membranes and excess mucus production. Increased blood volume also puts pressure on blood vessels in the nose and sinuses, which can also contribute to congestion.

Read here for a deep dive into Pregnancy Induced Rhinitis and what you can do about it during pregnancy.

Your hair may grow faster and become thicker. This is because hormonal changes cause hair to remain in a growth phase for longer than normal, causing you to shed less hair. Contrary to popular belief, thicker hair in pregnancy is not due to prenatal vitamins. After delivery, the drop in hormone levels signals a shift that makes hair follicles shed hair faster. This is known as postpartum hair loss (Telogen effluvium), typically occurring in months two through four after delivery. While hair shedding can be significant, you will not go bald, and your hair will grow back over time.

The placenta and ovaries release a hormone called relaxin during pregnancy, which causes joints and ligaments in the body to become more flexible. This benefits the pelvis by allowing the midsection to widen as your fetus grows. However, this can also cause instability in your joints, which can cause aches and pains. This also means you may need to be more cautious with your movements and physical activity during pregnancy because muscles and ligaments are easier to strain.

Your feet can grow wider and longer— up to a whole size— during pregnancy, and that change may be permanent. It’s suspected that relaxin is also the cause of this body change. You can read more about foot changes during pregnancy here .