What to Expect During Pregnancy: Third Trimester

The third trimester of pregnancy can often be the most challenging for women. As the baby finishes growing, your body begins preparing for delivery and many of the light affects of pregnancy during the second trimester make way for more intense changes.

Contact your doctor if you experience:

  • Bleeding (this could signal preterm labor or other serious problems)
  • Severe dizziness, abdominal pain, cramps, nausea, or vomiting
  • Rapid weight gain or too little weight gain
  • Pain or burning during urination (this could be a sign of a urinary tract infection)

Changes in your body during the third trimester

During the third trimester, your body can undergo the following changes:

Breast enlargement

Close to the baby’s due date, your breasts will have become enlarged and may begin discharging a yellowish substance from the nipples. This is called colostrum, which will nourish the baby during the first few days of life. Breast enlargement can cause back pain, so it’s important to wear a supportive bra.

Swelling

Mild swelling due to water retention may occur in the ankles, hands and face during the third trimester. Elevating your feet when sitting or sleeping can be helpful. If you experience sudden swelling, call your doctor right away – it could mean a pregnancy complication called preeclampsia.

Related resource: Preeclampsia handout

Weight gain

It is normal to gain ½ to 1 pound a week during your last trimester (consult with your doctor about your target weight gain range). This weight includes the baby’s weight, placenta, breast tissue, increased blood flow, amniotic fluid and other fluid.

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