Pregnancy-Related Changes

Why the body changes in pregnancy

• Hormones: hCG, estrogen and progesterone rise sharply. Progesterone relaxes smooth muscle throughout the body, slowing digestion and relaxing blood vessels and ligaments.
• Blood volume increases by about 40 to 50 percent, and the heart pumps more blood.
• The growing uterus presses on the stomach, bladder, bowel, diaphragm and large veins.
• Weight gain and a shifting center of gravity strain the back and pelvis.

Changes by trimester

First trimester (weeks 1 to 13)

• nausea and vomiting ("morning sickness," which can happen any time of day), usually easing by 14 to 16 weeks
• tiredness
• tender, swollen breasts
• frequent urination
• food cravings or aversions, a metallic taste, and heightened smell
• mood swings
• light spotting around implantation in some people
• bloating and constipation

Second trimester (weeks 14 to 27)

• nausea and fatigue usually improve
• a growing bump and weight gain
• first baby movements felt around 16 to 22 weeks
• round ligament pain: brief sharp pain in the lower belly or groin when moving
• skin changes: darker nipples, a dark line down the belly (linea nigra), and patchy facial darkening (melasma)
• stretch marks
• nasal congestion and nosebleeds
• bleeding gums

Third trimester (weeks 28 to birth)

• heartburn, as the uterus pushes up on the stomach
• back and pelvic pain, including pelvic girdle pain
• shortness of breath with exertion
• swollen ankles and feet, worse at the end of the day
• leg cramps at night
• Braxton Hicks contractions: irregular, painless or mildly uncomfortable tightening
• frequent urination and leaking urine when coughing
• hemorrhoids and varicose veins
• carpal tunnel syndrome: tingling and numbness in the fingers
• trouble sleeping

Normal or not? Common symptoms compared

Managing common discomforts

• Nausea: small frequent meals, plain crackers before getting up, ginger, and vitamin B6. Ask your doctor about medicines if it is severe.
• Heartburn: smaller meals, avoid lying down for 2 to 3 hours after eating, raise the head of the bed. Calcium-based antacids are generally safe.
• Constipation: fiber, fluids and activity. Bulk-forming laxatives are safe.
• Back pain: good posture, supportive shoes, a pregnancy support belt, physical therapy, and sleeping on your side with a pillow between the knees.
• Swollen ankles: raise your legs, avoid standing for long periods, compression stockings, and sleep on your left side.
• Leg cramps: calf stretches before bed and staying active.
• Headaches and pain: acetaminophen (paracetamol) is the usual choice. Follow the label dose. Avoid NSAIDs such as ibuprofen, especially after 20 weeks, unless your doctor advises them.

Emotional changes

Mood swings and worry are common. But persistent sadness, anxiety, loss of interest, or thoughts of self-harm can be signs of perinatal depression or anxiety, which are common and treatable. Tell your provider. In the US, the National Maternal Mental Health Hotline (1-833-852-6262) is available 24 hours a day.

After birth

Most changes reverse over the weeks to months after delivery. The uterus shrinks back over about 6 weeks, swelling goes down within days to weeks, and skin darkening usually fades. Stretch marks fade but often remain. Some changes, such as pelvic floor weakness, benefit from specific exercises or pelvic floor physical therapy.

Frequently asked questions

What body changes are normal in early pregnancy?

Common early changes include nausea, tiredness, tender and swollen breasts, frequent urination, food aversions or cravings, mood swings, bloating and constipation. Light spotting around the time of implantation can also occur.

Is swelling normal during pregnancy?

Mild swelling of both ankles and feet is normal, especially in the third trimester and at the end of the day. Sudden swelling of the face or hands, or one swollen, painful leg, is not normal and needs prompt medical care.

When should I worry about symptoms during pregnancy?

Seek urgent care for vaginal bleeding, severe headache or vision changes, chest pain, trouble breathing, fever, fluid leaking, regular contractions before 37 weeks, reduced baby movements, or thoughts of harming yourself.

Why does pregnancy cause heartburn?

Progesterone relaxes the valve between the stomach and esophagus, and the growing uterus pushes on the stomach. Both let acid move up into the esophagus. Smaller meals, avoiding lying down after eating, and safe antacids help.

Do pregnancy skin changes go away?

Most do. Darkened nipples, the linea nigra and melasma usually fade within months after birth, though melasma can persist. Stretch marks fade to a silvery color but rarely disappear completely. Sun protection helps prevent melasma from worsening.