Your Third Trimester of Pregnancy

The third trimester of pregnancy can be both physically and emotionally challenging. During this final stage, you may experience some of the symptoms from early pregnancy, such as fatigue and frequent urination (need to pee), along with new ones like Braxton-Hicks contractions and increased aches and pains. It’s common to feel anxious but understanding what to expect and how to care for yourself can help ease the discomfort and worry.

How long is the third trimester?

The third trimester typically lasts between 9 to 13 weeks, starting at week 29 and continuing until delivery, which usually occurs around week 40. Your baby is considered full term at the end of week 37.

Common symptoms in the third trimester

As your baby grows, your body undergoes significant changes that can cause discomfort. It’s important to take care of yourself as your baby completes their development. Expect to experience the following symptoms as your pregnancy progresses:

You may notice the following symptoms as you get closer to delivery:

• Baby “drops” (baby settles lower in your pelvis)
• Increased baby movement
• Braxton-Hicks contractions (false contractions)
• Fatigue
• Difficulty sleeping
• Heartburn
• Hemorrhoids
• Swollen ankles, fingers, or face
• Larger and tender breasts
• Leaky breasts
• Lower back and hip pain
• Pelvic pain
• Frequent urination
• Shortness of breath
• Darkening of nipples and areolas
• Sciatica (tingling or pain in the lower back, buttocks and legs) 

While you don’t feel it, as you near your due date your cervix becomes dilated and effaced to get ready for delivery. Here’s how to know when you’re in labor.

While some discomfort is normal, certain symptoms may indicate a problem. Contact your health care provider immediately if you experience:

• Vaginal bleeding
• Severe swelling
• High fever
• Painful contractions that increase in intensity
• Burning during urination
• Sudden weight gain
• Significant decrease in baby’s movement
• Vomiting 

Baby’s Development in the Third Trimester

Your baby is rapidly growing and preparing for life outside the womb. By the end of this trimester:

• Your baby will be around 19 to 21 inches long and weigh between 6.75 and 10 pounds.
• The brain is developing at a fast rate, and bones are hardening.
• By week 36, your baby should be in a head-down position, ready for birth.
• By week 37, your baby’s organs are mature enough to function on their own. 

Third trimester prenatal care

During the third trimester, you will visit your doctor more frequently—about every two weeks until week 35, and then weekly until delivery. At each visit, your doctor will:

• Collect a urine sample
• Measure your blood pressure and fundal height (the size of your uterus)
• Ask about your baby’s movement
• Check your cervix for dilation (opening) and effacement (thinning)

Around week 36, your doctor will test you for Group B strep, a bacteria that can affect newborns and requires treatment with antibiotics during labor. At this time, your doctor will also confirm if your baby is in the head-down position for birth. 

Preparing for delivery: Third trimester checklist 

As you approach the final weeks of pregnancy, it’s important to stay active and continue healthy habits. Walking throughout the day can help alleviate discomfort. You should also prepare for your baby’s arrival by completing the following tasks:

• Develop a birth plan with your doctor
• Decide on pain relief options for labor
• Schedule postpartum appointments
• Tour Banner Health’s maternity ward and pre-register for delivery
• Attend prenatal and breastfeeding classes at Banner Health
• Pack your hospital bag 
• Plan your route to the hospital
• Choose a pediatrician
• Decide on circumcision if applicable
• Install the car seat
• Wash your baby’s clothes and linens
• Stock up on baby supplies like diapers and wipes
• Check smoke and carbon monoxide detectors
• Make arrangements for other children or pets
• Prepare freezer meals for after delivery 

Learn more about Banner Health’s pregnancy resources

Banner Health offers a wide range of resources to support you during your pregnancy, including prenatal classes, educational materials, and support groups. Visit Banner Health’s Pregnancy Resources to learn more and help you feel prepared for this exciting time.

By taking the time to prepare, you can reduce stress and focus on the joy of welcoming your new baby.